I have this problem quite often, specifically I'll frequently decide I won't like something before I even try it, even if historically I've had enjoyment from it.

Often I just force myself to start, sometimes that's setting a line in the sand "I'm going to watch YouTube until 15:00 and then we're going to do X" other times is physically forcing myself (setting alarms, sleep timers, etc..)

I don't really have a magic bullet unfortunately beyond "Just do it" but honestly getting over the hump is 99% of the problem.