Do you recommend Medicare or Advantage plan when going into MC facility? Healthy otherwise, now on Advantage plan.

It goes by state. In my state it's called MSHO (Minnesota Senior Health Options) and my LO needs to enroll every year. It is a combo of Medicare and Medicaid. Many major carriers (like BCBS, Medica) offer plans. Advantage is not one of them that I'm aware of in my state. My MIL's chosen plan gives her access to the same clinic network that I use and trust. All of her care (including dental) happens inside her facility. She has received excellent care in her LTC facility -- even being on hospice for covid, which she survived, thanks to her good care.

Once on MA he cannot change to regular Medicare except for an instance if in the first year. Unless he moves to another state to re enroll but still iffy. Talk to a Medicare insurance agent to find the best plan under MA. They should not cost you anything. Bring his list of meds with you.You just massed the enrollment pariod. At least in MC he can get a tax deduction. You have to see an accountant for that info.
Now when mom was in MC, there was a visiting doctor service for regular Medicare only. But specialists and emergencies required transpot. She was on MA but I was able to drive her. I knew if she ever became non ambulatory that she would go to a SNF

I personally would not be on an Advantage plan but if it works then stay on it.