Whether it's school, work, or family. I'm always stuck with some rude person or another. I'm young (19M) so a lot of people older than me speak to me in a way I do not deserve to be spoken to. They don't speak to people their own age that way.

I just hate being stuck and forced to have to just sit quietly and tolerate all this bullshit all the time.

Today my colleague (he's "training" me btw) kept making fun of my work and picking apart my flaws in front of everyone and laughing about it. I didn't say anything, and then he proceeds to say that I should accept my mistakes, to which I say I'm not perfect. He goes, "yeah, you're not.". He only picked the pieces of my work that had mistakes and conveniently ignored all the successes. Not to mention this absolute douchebag didn't actually train me jack shit, I learnt purely by my own observational skills. All he does is make fun, zero constructive criticism.

Then since I didn't know apparently a fight broke out in the second floor the other day he asks twice if I do drugs (what the fuck?) . I'm introverted, imaginative, focused on my goals, and I'm completely disinterested in the people at my workplace. He has the audacity to tell me to "change". It's very common here. I absolutely fucking despise these people who think they're the experts on my life just because they're older. I'm fine just the way I am, thanks very much. Maybe you need to work on your manners.

The asshat knows he's being dubious because he only says shit like this in a low voice. I'm going to ignore him or ask him to repeat himself several times, say I can't hear him, or stare him straight in the eyes for a few seconds and turn away.

Dont suggest reporting him. It doesn't work that way here. It'll only complicate things for me.