There are 2 forms (available thru Social Security) that need to be completed to activate your Part B (outpatient) benefits. One form is completed by you; the other is completed by your employer; both forms need to be taken to Social Security for enrollment onto Part B. Your new enrollment allows you a special election period any time during the year, no penalty.
Once you are enrolled onto both Part A and Part B of Medicare you have choices: (1) you can add a Medicare supplement/medigap policy, if you want freedom of choice when selecting providers, along with a stand alone prescription drug plan; (2) you can select a Medicare Advantage/HMO plan (i.e., all of your doctors would need to be in the same medical group and take the HMO plan you select) – the HMO would provide both your medical and prescription drug coverage; or (3) if your company has a retiree plan that contains prescription coverage and states in their plan document that the drug coverage is deemed comparable to a Medicare drug plan, you can go ahead and partner that retiree plan with your Part A and B of Medicare.