Is there an elevator from floor to floor?

Yes

Yes it is located by the restrooms

Yes, but sometimes hard to stay on the right path if you need the elevators.

Absolutely

There's elevators throughout but if you're unsteady on your feet, there are some uneven floors in some of the exhibits

Plenty of room for your wheel chair. ALL will be expressed. My dad was thier. WW11.

Yes, there are multiple elevators and ramps to help you navigate the exhibits.

Is very handicapped friendly wheelchairs handrails bathrooms handicap friendly

Yes. There are multiple elevators that are easy to find. You should have no problem using them to go through the museum.