I work from home because I live 500 miles from my firm's office. I was recruited as a remote employee before COVID and used to fly to the office every week on Sunday night and fly home Thursday morning. It was rough but doable. The one good thing COVID did was normalize online meetings, so now I fly to the office once every 4 or 5 weeks for key meetings.
Anyway, I run about 70 miles a week, but noticed I was having a tough time justifying gym time on top of that. I am a husband and father, so at a certain point it just felt selfish to be working out that much. So I got some 25-pound dumbbells, a pull-up bar, and some of those push-up handle things. I think I do about 90 seconds on one of these about every hour. Nothing huge, but one day I managed 125 push-ups, 40 pull-ups, and 200 bicep curls. I don't stress about it and rarely count, but it has made a big difference over the past year. Not huge gains, mind you, but just general arm and chest strength and the way it makes me feel.
Lastly: the best investment in fitness I have ever made was a standup desk. Game changer. Sitting is terrible. I am standing right now and about to go do 25 curls, 10 pull-ups, and 20 push-ups.