While the main attractions in Key West Florida are fairly close together, for those who have difficulty walking or pushing a wheelchair long distances, there are some options for getting around.
The Old Town Trolley Tour has some information on their website about accessibility (https://www.trolleytours.com/key-west/accessibility-safety). While not all of the trolleys are accessible, many are – but contacting the company in advance is recommended. Also, not all of the stops are accessible, so be sure to read their website in advance.
For spot to spot transportation, Key West Taxi hass wheelchair accessible vehicles available. However, since not all of their vehicles are wheelchair accessible, getting in touch beforehand is recommended. https://www.keywesttaxi.com/contact
I went to Key West ages ago with my family. We rented a van from Miami and drive there, but if I remember correctly, we parked and spent most of the time walking/wheeling. So, that is an option too if you don’t mind the heat!
Here is a video we shot in Key West. We did well with my wife’s wheelchair. For the conch train, she is able to walk a short distance and was able to get in the car, and then they stored her chair on board. https://youtu.be/aJNlYpzsM2E