If you have paid into Medicare and Social Security for, what I believe is 40 quarters, thru payroll taxes then you will automatically be enrolled in Medicare when you turn 65. You should receive something in the mail from them 3 month prior to your birthday... you have to "opt out" of part B, otherwise the premium for part b, @ $100 monthly, will be deducted from your Social Security check. When do you turn 65?