Part D Prescription Coverage
Medicare alone doesn't cover prescriptions, so you'll need to make sure that you have enrolled in prescription coverage, too. If you're enrolling in a Medicare Advantage Plan (Part C) as your supplement, prescription benefits are included. But if not, you'll want to enroll in Part D.
You can only enroll between October 15th and December 7th of each year for a Part D Prescription Plan. Other enrollment times include when you are first eligible for Medicare and when you lose qualified coverage (like through your job-based coverage). If you don't enroll, you'll likely pay a late enrollment penalty.