So sorry you are so worried about your Mayo visit. Many of us go to our appointments alone. I prefer it. And with Covid it was not the case to increase risk.
For procedures where I require someone to pick me up, I arrange with family. Otherwise, I would call "Visiting Angels" mentioned in one of the above posts and hire one of them. They provide qualified helpers to assist patients.
Regarding getting around, where are your appointments? The Gonda and the Mayo Buildings are more like the same building, just different elevators. Right next to them is the Methodist Hospital combined with other buildings with different specialties. A hotel like the Kahler Grande is across the street - five second walk to Gonda Building
Hotels have room service, but the sub level cafeteria in the Gonda Building is cheap and good. Wheelchairs are available everywhere so no problem to get one.
As far as absorbing everything the doctors say. establish an account on Mayo MyChart. The Doctors post their notes on the visit and all tests' results must be posted by law. That is very informative, and you will want to read results. Also you might engage your local Primary Care Provider to help you get through the documents.
Also remember Mayo is a teaching hospital and research institution. The "big cheese" doctor will see you for the major component of a visit, but you will have preliminary and follow-up by attendants, interns, PAs and nurses. There are many patients requiring attention, so it is a management technique.
Mayo is unique in its organization and scheduling follow-up appointments. You will be impressed.