So how did folks manage before there was a New Testament? Such as during the early weeks, months and years following the Ascension of Jesus? Read Acts 15, for instance. A dispute arose in Antioch over the question of circumcision. Paul and Barnabas returned to Jerusalem to consult "the Apostles and Ancients". It was the Church, not a book, which gave a ruling.
The early Christian communities, such as those at Antioch, couldn't say "let's see what the New Testament says". There wasn't one.
First came the Church. Then came the New Testament. Not the other way around. The New Testament didn't drop out of the sky when Jesus ascended. The documents which are now contained within it, first had to be written, then collected and assembled, then distributed. In the interim, life went on. For quite some time. The Gospel was preached, disputes were settled, evangelists were commissioned. All without out a single New Testament.
The day of Pentecost finds 3000 people saved without Peter saying ONE WORD about an infallible Church putting its approval on what he preached. As a matter of fact, there is no place recorded that said that Christians, who "went everywhere preaching the Word" (Acts 8:4), needed or expected an infallible Church that existed to endorse the gospel, and verify that the gospel was true.
And then it ended up in the 'book'... You're even close...The Apostles were not and are not the 'church'...And there was no (C)hurch...And still isn't...Your Catholic clergy and institution are not the church of the bible, nor the Apostles...