However, you do not have to enroll in any other Medicare programs.
The only intersection of the SS and Medicare programs is when you turn 65 and Medicare Part A is mandated.
You will also be signed up for Part B but you can decline it to keep them from withdrawing $120 a month from your SS check every month.
I was 62 so perhaps that is why I did not need to sign up until no longer covered by my wife a few years later