I would suggest trying another IT job before deciding to switch careers. The place you are at now sounds incredibly toxic and may be turning you off IT. Your boss is mean and the HR person doesn't sound much better. If there's someone in charge of sending people off to these apprenticeships (I have no idea how that works where you are), I might let them know that this is an unsupportive environment for a new worker. Of course you need someone to show you the ropes - that's why it's called an apprenticeship!

You can get ahead very quickly in IT (and most fields, really) by having empathy and wanting to help people. Could you get an IT job for now in an organization that's mental health related so you could scope out the kind of mental health jobs you might like? Or get a non IT job in that field to make sure you like it before you devote more time to school?