

As always, everyone’s experience varies, but having ADHD I’ve always found the best way to get yourself to do something long term is to make it a super ingrained habit. I usually say 8 weeks is a good minimum to get it ingrained, and while I’ve had breaks, I generally find it much easier to get back to the swing of the habit if I have to take a break from it (or forget one of my exercise days).
Don’t forget, most computers are faster on Linux than on the newest windows version, so you can hold off on upgrades for longer if the hardware is physically fine, which just further decreases costs.