I've a little experience with this with older teens. I'd argue that she is the one who has to make herself go, to get over her anxiety, and that forcing her and resorting to carrying her or physically fighting means she's not well enough, but with the proviso that she needs to make some effort to plan for the future.
Can you homeschool? Some people I know have done that, or the school has adopted Goole Classrooms for older teens to use at home, part time, and only go into school certain days, or half days, a week.
Is there an alternative form of transport she'd prefer, and are there any school friends she could go to school with? Sometimes the anxiety is abour the journey itself.
It sounds as if one possibility mught be to do with your relationship with her, and how she interprets your actions (perhaps as controlling) which a lot of teens fight hard against. If this is the case, try to get her talking about her feelings and see if there is a compromise which helps her feel more trusted and in control of her life, conditional upon her meeting expectations of getting ready and to school on time herself. Easier said than done, and can take a long time for some teenagers (and parents) to find the words to use in these circumstances.