Tips for finding reliable employment

Hello
I’m 20 years old and I am so sick of “Highschool” type jobs. In the last year I’ve worked at a grocery store and a restaurant, both of which hired me on “full time” but treat me as a Highschool student, and make me part time like everyone else younger in the building, since most of them are high school. I’m struggling because I live 6 hours away from my hometown/family , so I’m sick of being lied to, and being given 20ish hours a week. My most recent employer even lied about my pay rate. I’m begging if anyone has any ideas of what I could do job wise that will take me seriously, be reliable and give me real hours, I would appreciate it. I will do anything. I have experience with regular computer work and graphic design as well.