hi @LeTimBo tim. great to see a personal note from somebody - but it’s uncommon in this forum as it is too huge and majority of the users don’t come back once their issue is fixed. Nevertheless I’m willi I’m regular user, one of the moderators of the forum and I wish you all the best with your new profession, I’m working in telecom/IT since 20 years and still find it demanding and interesting - definitely not a bad choice!
Unfortunately I can’t really help you. I don’t have 32-bit system handy (and nobody should today 
). I can’t believe mentioned occ command is harmful (by itself it is not, unless there is some other bug).
You mentioned multiple issues already: deprecation of 32-bit (but major bugs should be sorted out in 25.0.2 - 25.0.3 is not released now) and PHP 7.3 - which definitely unsupported with NC 25 (and out of PHP support for a year I believe). I wonder about 7.3 - I was under impression Debian 11 comes with PHP 7.4 (which is out of security support now). I would start upgrading PHP to 7.4 at least, but strongly recommend 8.* or you have a chance migrating to a 64-bit server…
good luck!