Is there any type of grant for an 80 yr old retired VA Vet for home modification and in home family caregiver?

The VA used to and still may have grants for home improvements.   I'm not that familiar with caregiving allowances, but the first step is to contact your area's VA, county or state VA office, or local VFW or American Legion branch to help explain what benefits are available.

If this Veteran is already getting benefits, you'll need to determine to what team he's been assigned, then contact the social worker for that team.   If you don't have access to qualification and correspondence documents identifying his team, you may have to call the local VA or the VA where he qualified to get that information.

I found the SWs to be very, very helpful and knowledgeable.

You can start here:

https://www.google.com/search?source=hp&ei=ipEEYK2DNpOqtQbS47P4Dg&q=Louisville%2C+KY+VA+regional+office&oq=Louisville%2C+KY+VA+regional+office&gs_lcp=CgZwc3ktYWIQAzIOCC4QxwEQrwEQyQMQkwIyBggAEBYQHjoLCC4QsQMQyQMQkwI6AggAOggIABCxAxCDAToFCAAQsQM6BQgAEMkDOgIILjoLCAAQsQMQgwEQyQM6CAguEMcBEK8BOgQIABAKULwMWOdGYOBHaABwAHgAgAHsAYgBzRCSAQYxMS44LjGYAQCgAQKgAQGqAQdnd3Mtd2l6&sclient=psy-ab&ved=0ahUKEwit8LWu26PuAhUTVc0KHdLxDO8Q4dUDCAw&uact=5#spf=1610912148661

or search on "Louisville, KY VA Regional Office".

Good luck; I hope you find some sources of assistance.

Others have great suggestions, and also call your Area Agency on Aging. Some states have programs for seniors that help with home modifications- even if you don't qualify for Medicaid. But it is completely dependent on local availability, so you have to contact the AAA where he lives. https://www.agingcare.com/local/area-agency-on-aging

Home Depot has a Veterans grant of $5k you can apply for home modofocations. Most work and paperwork would be done by a local non-profit.

You can find more info here or email them to see who administers grants in your area

https://corporate.homedepot.com/community/home-depot-foundation-grants

Call the VA and ask about Aid and Attendance. There is a stipend that would be paid if he qualifies by serving during war time.