Definitely. If you find walking steps difficult, wait by wheelchair sign and you can walk up the r amp. On Magical Express if having trouble with steps, when booking ask for wheelchair assist. You will need to transfer to a wheelchair - the lift actually rides up and standing isn't allowed. Your wallker will be placed underneath the bus. You would retrieve it at the resort.
If you don't have transportation double navigating steps, just wait in regular lines and for your walker.