Help me stay in school

Pls help me. I am currently in high school (won't tell my real age tho because of safety) and am currently kinda screwing up at life. I always had issues with impulse control, an have been diagnosed with ADHD (which I take meds for.). After being kicked out of like five schools, This year, I got into a boarding school in Massachusetts which honestly was a really good turn of events since this is a pretty good school. I have friends there, have a decent dorm life, but am having trouble staying focused and completing my homework. The schedule is very strict, and barely any deviations are allowed. every night, we get 2 hours to complete all our homework, and then its time for bed. The school issued s chromebooks, and, as a child who has really tech- restrictive parents (I only have a phone and a gaming computer that a friend gave me), this was a rare opportunity for me. I am obsessed with video games, so, instead of doing my homework and shit, I will sit on my bed and play games or watch videos. I will horribly procrastinate. Sometimes, I even found myself cutting class to watch a dumb video about who-knows-what. I also can't stop lying by the way, I even find myself lying about little things. Also, I constantly can't keep my mouth shut and am very rude and snarky, talking back to teachers. So then, last Friday, I got called up to the main office who told me I would be going home to take a "break" from school. They said it was so I could get my meds sorted, but my parents said I was getting kicked out and constantly guilt trip me, saying that the only next place for me is a mental institution. Also, they lie a lot and I never know if they are telling the truth. One of them has touched my gaming computer, but honestly, whatever, I'll get it back sometime. I just need help getting back in and proving to everyone, including myself, that I can do it and am not a mentally ill idiot.