Prior qualifications? Depending on the Order/Congregation, usually none are necessary - i.e. you can go in straight outta school (so I guess, highschool diploma of some kind is necessary but not always).
Then you enter into the Order/Congregation as an Aspirant, and for the next 5-11 years (depending on the Order) you “train” and discern etc. Then you make final vows and you become a “Brother”
contact the vocations director of your diocese who can help you contact various religious orders who include religious brothers, or consecrated single men who are not priests.
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