General Discussion

He's making the grim face while going up those steps because of the pain he's in. Also he has trouble balancing, so he's holds both left and right railings. The helicopter steps could be due to some air currents or buoyancy while he tried to climb up. It's not necessarily a sign of weakness or old age.

Yes Chump definitely has trouble with any kind of steps. He only uses an elevator in the White House and in Mar-A-Lago. The only time he uses steps is when he gets on and off Air Force One or the helicopters. Sometimes he might pose for a photo on steps but he doesn't actually go up or down.