that's a great question and many people in your situation have been wondering about this. the good news is if you are already covered by medicare you are all set. you needn't worry about the new health insurance marketplaces or any changes to your existing coverage.
i am 89 and have the usual medicare insurance and an additional coverage from the firm i worked for. my wife is 80 and has the usual medicare insurance and additional coverage from the state of north carolina. do we have to change to something else?