I entered yes when asked if I had marketplace health insurance. I need to change the answer to "no" since I had Medicare, but cannot find the question. Help, please.

Refer to the TurboTax article Where do I enter my 1095-A? and follow the navigation instructions (if using TurboTax Online or Mobile, select  the link). The link will take you to the Deductions and Credit section where you can delete the 1095-A.

When in Turbo Tax go to FEDERAL TAXES then select DEDUCTION & CREDITS page down to MEDICAL select AFFORDABLE CARE ACT update and select NO, I DID NOT RECEIVE FORM 1095 A then select CONTINUE and follow Turbo Tax instructions.

Thanks for your help. I am all set now. I appreciate your response. 

Thank you very much!