That not scripture is all you need. And the conclusion you draw ignores most of the New TEstament which shows Jesus picking Apostles and instituting sacraments like confession and communion. If these things are unnecessary then why would they be mentioned in the Bible?
Nowhere is regular confession to Catholics priests commanded or shown in the NT, nor receiving the Catholic wafer-god , while by your own logic, if such were necessary then why would they not be mentioned in the Bible?
For the first Christians were those of the New Testament (NT) church. Which church, as manifested in the only wholly inspired-of-God substantive record of what the New Testament church believed, which is Scripture, in particular Acts through Revelation, which best shows how the NT church understood the gospels.
1. Was not based upon the premise of ensured perpetual magisterial infallibility of office as per Rome, which has presumed to infallibly declare that she is and will perpetually be infallible whenever she speaks in accordance with her infallibly defined (scope and subject-based) formula, which renders her declaration that she is infallible, to be infallible, as well as all else she accordingly declares.
2. Never promised or taught ensured perpetual magisterial infallibility was essential for preservation of truth, including writings to be discerned and established as Scripture, and for assurance of faith, and that historical descent as the stewards of Scripture means that such possessed ensured infallibility.
3. Never was a church that manifested the Lord's supper as being the prominent paramount practice as the central means of grace, around which all else revolved, it being the source and summit of the Christian faith in which the work of our redemption is accomplished, by which one received spiritual life in themselves by consuming the real flesh and blood of Christ under the appearance and manifest materialism of non-existent bread and wine, even to the smallest particle (until such begins to decay, at which point Christ also is said to cease to exist under that appearance). Which is in contrast to preaching the word being the primary active function of pastors (see below). And with the Lord's supper, which is only manifestly described once (besides feast of charity in Jude 1:12) in the inspired record of the life of the church, focusing on the church being the body of Christ in showing the Lord sacrificial death by that communal meal.
4. Never had any pastors titled "priests" as denoting a separate sacerdotal class (and (thus translating the distinctive Greek word for such, hiereus, as priest, but which word the Holy Spirit never used for NT clergy, as all believers are called to sacrifice (Rm. 12:1; 15:16; Phil. 2:17; 4:18; Heb. 13:15,16; cf. 9:9) and all constitute the only priesthood hieráteuma in the NT church), whose unique sacrificial function was that of confecting the Eucharist, turning bread and wine into the body and blood of Christ and offering it as a sacrifice for sin, and dispensing it to the people as spiritual food, versus preaching the word being their primary active function, (2Tim. 4:2) eeding the flock thereby (Acts 20:28)
Which alone is said to spiritually nourish souls, (1Tim. 4:6) and which builds them up. (Acts 20:32) with believing the gospel being the means of obtaining life in oneself, by which one is regenerated, (Acts 10:43-47; 15:7-9; Eph. 1:13) and thus desiring the milk (1Pt. 2:2) and then the strong meat (Heb. 5:12-14) of the word of God, thereby being nourished (1Tim. 4:6) by hearing the word of God and letting it dwell in them, (Col. 3:16) by which word (Scriptures) man is to live by, (Mt. 4:4) as Christ lived by the Father, (Jn. 6:57) doing His will being His meat. (Jn. 4:34)
5. Never differentiated between bishops and elders, and with grand titles ("Most Reverend Eminence," Very Reverend, Most Illustrious and Most Reverend Lord, His Eminence Cardinal, The Most Reverend the Archbishop, etc.) or made themselves distinct by their ostentatious pompous garb. (Matthew 23:5-7) Or were all to be formally called father as that would require them to be spiritual fathers to all (Mt. 23:8-10 is a form of hyperbole, reproving the love of titles such as Catholicism examples, and thinking of men above that which is written, and instead the Lord emphasizes the One Father of all who are born of the Spirit, whom He Himself worked to glorify).
6. Never required clerical celibacy as the norm, (1Tim. 3:17) which presumes all such have that gift, (1Cor. 7:7) or otherwise manifested that celibacy was the norm among apostles and pastors, or had vowed to be so. (1Cor. 9:4; Titus 1:5,6)
7. Never taught that Peter was the "rock" of Mt. 16:18 upon which the church is built, interpreting Mt. 16:18, rather than upon the rock of the faith confessed by Peter, thus Christ Himself. (For in contrast to Peter, that the LORD Jesus is the Rock (petra) or "stone" (lithos, and which denotes a large rock in Mk. 16:4) upon which the church is built is one of the most abundantly confirmed doctrines in the Bible (petra: Rm. 9:33; 1Cor. 10:4; 1Pet. 2:8; cf. Lk. 6:48; 1Cor. 3:11; lithos: Mat. 21:42; Mk.12:10-11; Lk. 20:17-18; Act. 4:11; Rm. 9:33; Eph. 2:20; cf. Dt. 32:4, Is. 28:16) including by Peter himself. (1Pt. 2:4-8) Rome's current catechism attempts to have Peter himself as the rock as well, but also affirms: On the rock of this faith confessed by St Peter, Christ build his Church, (pt. 1, sec. 2, cp. 2, para. 424) which understanding some of the so-called church fathers concur with.)
8. Never taught or exampled that all the churches were to look to Peter as the bishop of Rome, as the first of a line of supreme heads reigning over all the churches, and having the last word in questions affecting the whole Church.
9. Never recorded or taught any apostolic successors (like for James: Acts 12:1,2) after Judas who was to maintain the original 12: Rv. 21:14) or elected any apostolic successors by voting, versus casting lots (no politics). (Acts 1:15ff)
10. Never recorded or manifested (not by conjecture) sprinkling or baptism without repentant personal faith, that being the stated requirement for baptism. (Acts 2:38; 8:36-38)
11. Never preached a gospel of salvation which begins with becoming good enough inside (formally justified due to infused interior charity), via sprinkling (RC "baptism") in recognition of proxy faith, and which thus usually ends with becoming good enough again to enter Heaven via suffering in purgatory, commencing at death.
12. Never supported or made laws that restricted personal reading of Scripture by laity (contrary to Chrysostom), if able and available, sometimes even outlawing it when it was.
13. Never used the sword of men to deal with its theological dissenters.
14. Never taught that the deity Muslims worship (who is not as an "unknown god") is the same as theirs.
15. Never had a separate class of believers called saints.
16. Never prayed to anyone in Heaven but the Lord, or were instructed to (i.e. "our Mother who art in Heaven") who were able to hear and respond to virtually unlimited prayers addressed to them (a uniquely Divine attribute in Scripture).
17. Never recorded a women who never sinned, and was a perpetual virgin despite being married (contrary to the normal description of marriage, as in leaving and sexually cleaving) and who would be bodily assumed to Heaven and exalted (officially or with implicit sanction)
*Such as being a sinless perpetual virgin, who "had to suffer, as He did, all the consequences of sins," [De Maria Nun quam Satis] "in exact duplication," [Mary of Agreda] and was bodily resurrected and crowned as an omnipotent (by God's grace) Queen of Heaven, whose command all obey, even God [Alphonsus Liguori], as "the greatness of the power which she wields over one who is God cannot be conceived," with angels "begging her as a favour to honour them with one of her requests," [Montfort] ...and the dispenser of all graces, with there being "no grace which Mary cannot dispose of as her own," [Manteau-Bonamy] that "through her are obtained every hope, every grace, and all salvation...we obtain everything through Mary," [Pope Pius IX] with "all the treasures of the mercy of God" being in her hands, [St. Peter Damian] without whom the Holy Spirit does not act, and who is actually like unto Him "when she acts, it is also He who acts; and that if her intervention be not accepted, neither is His," who is the "Mother of her Creator," [Cardinal Newman] who is is a debtor to her, [St. Methodius] and who "could not be more closely united to God without becoming God," who alone is solicitous for us in Heaven, [Liguori] thus sometimes salvation is quicker if we remember Mary's name then if we invoked the name of the Lord Jesus" [Eadmer] "therefore we have recourse, to thee alone" [Liguori].