Partially true. A permanent deacon is an ordained clergyman in the Church, not a layman. And deacons have some restrictions on marriage. If single at the time of ordination, they take the same vow of celibacy as a priest. If married at the time of ordination, they take the vow to not remarry should their wife die.
Sorry for the redundancy. Didn’t see your post.
A deacon receives the Sacrament of Holy Orders and is ordained, and is therefore a clergyman.
If a deacon is married at the time of ordination, he remains married; but does not remarry if his wife passes away: a widowed deacon must remain unmarried. Also if he is unmarried at the time of ordination, he must remain unmarried (celibate.)
Formerly,the Catholic Church had "Major Orders" (bishop, priest and deacon/subdeacon) and "Minor Orders" (acolyte, exorcist, lector and porter/usher.)
In 1972, the minor orders were renamed "ministries" and are now carried out by laypeople, both men and women: now it's just lector, acolyte and usher.
Exorcist is a special, rarer role with extensive specialized training. I don't think all dioceses have an official exorcist, but Pope Francis is encouraging the expansion of the Order of Exorcists. I believe an exorcist is always a priest.
Traditionalist Catholics who use the 1962 Roman Missal still observe the traditional Major Orders (considered clergy) and Minor Orders (considered laity). I'm thinking maybe Eastern Rite Catholics do too (??)
That's the basic outline, but I may be a little fuzzy on the details. It's shifted a bit over the last century.
Thanks for the correction.