They are an Institution that have autonomy on imposing a dress code like any other institution in India. Muslim women who wants to wear face veil can look for Muslim schools that allow it. There are prominent Christian Schools that don't allow wearing any sorts of religious symbols including head scarf, cross etc... It's up to their parents where they want to send their kids.
A school management can impose a certain way of dressing for students. I can't say I shouldn't wear red coloured uniform, I can wear whatever I want, it's my fundamental right.
Nobody is stripping women ffs, just imposing a law in private institution.