Is it normal to take medroxyprogesterone every day continuously to treat endometrial hyperplasia with atypia?

Yes: With that diagnosis there is a 30% chance they are wrong and you actually have cancer. So normally you would take that medicine every single day for 3 months then repeat a hysteroscopy with d;c to make sure there is no sign of cancer or pre-cancer. Very serious issue.

Control biopsy: This can be done. I assume the plan is to repeat an endometrial biopsy after three months.