I've always found myself having trouble getting to work out if I didn't have some sort of tangible goal to achieve in the process. Like with walking, I need a destination to reach, like maybe going to pick up lunch or groceries. Same for other forms of body work outs, I've found vr games can be handy for giving me something to get lost in while still working out, like this one squatting game called hotsquats, or some of those rhythm games
Just doing a treadmill while staring at a tv doesn't keep my brain as engaged.
I tried to get back into using a bike last year but man.. what ever leg muscles did the most work with biking were just so terribly gone I could only make it one lap around a small park in my neighborhood. Didn't help that the bike seat dug in between the legs