For me, starting is the hardest part. I think that's true for a lot of people.
But then momentum builds and I might even become obsessed, completely consumed, in a state of flow.
How to start?
One way is to think of an easy competent task, write it down, and commit to spending just five minutes on it.
Set a timer and don't stop until it gets to zero. (Just Google "5 minute timer".)
Do this again. Then once or twice more. If it works, I'll ignore the timer and just continue working.
If not, I take a break and repeat.
Crucial to all of this is -- this is also the hardest part -- is staying free of distraction. I find calm, zen-like music helps. Lately, I Google "study music" and go with whatever comes up on YouTube.