Most sections of the Great Wall are not wheelchair accessible.
Some sections (including Mutianyu) have cable cars up and down the wall but from the parking lot to the cable car you still need to walk around 10mins, and you can’t ride the wheelchair. If you are not able to make the walk, our suggestion is to visit the Juyongguan Section of the Great Wall, the driver take you to the parking lot of the bottom of the Wall , there you can see the Great Wall without climbing all the steps.