Welcome!
I don't have any specific advice for you about metal buildings.
I can tell you that around the Richmond, VA area, there are several home type settings for senior citizens with varying accommodations for varying levels of independence. They start with small apartments where they have someone visit a couple times a week to clean, you have the option to eat/cook for yourself or eat in the cafeteria on the grounds. If your needs grow to needing daily visits from a nurse, they can accomdate that. They advance all the way to a full-blown nursing home with several steps in between. They have amenities available, like garden plots, swimming pools, recreation rooms, woodshops, etc. They also provide transportation on a regular basis for local shopping, medical appointments, etc. Perhaps your area has something like that.
What part of SE Georgia are you in? I went to college at GA Southern in Statesboro and was then stationed at Ft. Stewart for 4 years.