Why exactly do you hate Catholic school? You never even said. Are you even Catholic (we’ve had plenty of noncatholics attend purely for the educational value vs public school). Dress code? I remember having a former nun stand out in the hallway with a meter stick point out when shoelaces and shirts were untucked. Are you being bullied?
In retrospect I was glad my mom sacrificed to send me there. I had great teachers for 12 yrs. Good experiences. Are there cliques sure. But it is with any school. We bonded over trips, our wonderful retreats.
If you came from a public school to Catholic it may be an adjustment period. An LGBT issue? I’m straight but my hs has been nothing but welcoming, even had several on staff for decades. Even the people I knew as rebels who tried to test the nuns with their style or just be out and proud with sexuality have become VERY successful later in life. Later admitting to being hardheaded but relishing the experience, it guided them to give them a template to succeed later even when they half-assed school.
If there’s a chapel on the campus, go there. Sit in silence and ask of yourself and God what it is that is necessary to make this journey feasible for you. Seek one of the guidance counselors or spiritual directors. You will find they won’t judge you in the slightest. One sought me after I found out my grandmother passed away when I was a newbie freshman drowning in a student body of 800.
In fact I recall one instance where I was dropped off extremely early 430, 5am so my old man could go golfing. I was sleepy, exhausted and had exams. One of the nuns who a majority dubbed as a horror because she was quiet and stern, unlike our boisterous fun loving principal opened the door and let me in to the cafeteria by my locker. Turned on the light, got me a fresh free breakfast (nothing fr a vending machine). Sat down asked about my school work, why I was there so early, she was very sweet and motherly. Even gave me a blanket from our spirit shop to keep warm.
Really, this school is about your formative years. No need to be so negativistic even if you aren’t Catholic, nor agree with the politics of the Church. It will embrace you and guide you to adulthood if you let it.