It's OK to help someone apply for Original Medicare. You don't need to be appointed as a representative of the person, and you don't need to be related or an attorney.
If you're completing the application for someone else, Social Security may ask about:
Each Medicare plan can only cover one person, so the person you're helping needs to sign the application. If you're not in the same place, Social Security will forward it to him or her to sign.
If you need more information, you can learn more online on the Social Security website.