Moving from US to Spain

I have read so much I'm somewhat confused about what I need to do to facilitate my move.

I am semi-retired and on Medicare have medical issues so healthcare and medicine are  concerns.

I need to be pointed to a resource (s) that will explain the process, visas etc.  Possibly applying for citizenship, grandfather was Spanish.

I would love to hear from someone who can give me a head start.

Thanks

Hi. I just spent 3 months reading various websites, government and non, asking, searching . I really think it's the best to hire a lawyer in Spain specialized in immigration issues. Laws are changing often and it's hard to know it all, so do lawyer would be the best. Some of them sent me their fees for half an hour consultation that go from 50E to 200E. They all will deduct these fees if you decide to go through them. And of course, many of them speak English and work with expats from USA and UK.

Thanks for your info