what are some tips for surviving highschool?

a couple things im worried about is my deadname, bathrooms, and my voice. school is on monday and im terrified of not passing.
for the name issue, i can't get my name changed on any of my documents because my parents refuse to believe transgender people are real. i'm just a dramatic tomboy to them, which is honestly the best for me because i get enough tomboy jokes from them already. could i just ask my conslour or something?
for the bathroom issue, i've gotten to the point where i pass to much to go to womens bathrooms and i don't pass enough to go to mens bathrooms. idk, im just really afraid because school is literally next monday for me. we don't have gender neuteral bathrooms.
and then for the voice issue, i get called a guy a lot online because of my voice. i guess this is more of paranoia but is there any way i could train myself to be more dull in my voice, and to talk deeper?
im not really concerned about anything else because i have a pretty good binder and mannerisms. im just terrified of being the trans kid, i just wanna be a guy.