When buying your ticket ask you travel agent for assistant travel. It’s free.when you get off at your destination or if you go long hall and need to change planes they assist you
Most helpful if you struggle

I usually fly from Manchester UK with Jet 2, and the first time I took my walking stick, I was asked to take a seat, and not to worry about luggage check in. Within minutes, I was created in a wheelchair chair, taken to the front of the queue at check-in, then I was in their hands right up to being lifted on the plane, taken to my seat, and told to wait on the plane after landing, when they took me in a wheelchair and nothing was to much trouble for them!!!

I'd check with your doc to be sure you don't need to use O2 to fly. Wearing a mask is a good idea, and you simply ask for a wheelchair when you get to the counter to leave your bags. The wheelchair will get you through security quickly and then take you to your gate. Give yourself enough time to get a wheelchair; smaller airports especially don't have a lot of people to push them, so you need to be sure there's time to get you to security and to your gate. When they ask for people with disabilities to board, you go right ahead, even if you don't need wheelchair assistance to get on the plane.

I used travel assistance (COPD makes long walking difficult) at Manchester airport for a flight to Vancouver. The airline provided it at my request. Almost embarrassed by the amount of care that I was shown and I was wheel-chaired on and off the flight. Some waiting is involved for an assistant, but I had a trouble free 9 hour flight as a result. Well worth the booking if you have a breathing problem with exercise.Why spoil a holiday before it even starts?!

I recently flew from Orlando , FL to CT & requested a wheel chair. No problems. I reserved ahead of time. On my flight back with Southwest I had not reserved but I asked at the check-in counter & they immediately got me a wheel chair.