Personal motivation is a tricky thing...
I'm not a huge fan of Jordan Peterson or Jocko Willink... but I would be remiss to say that they didn't provide a modicum of decent life advice when they were relevant. They were the big two pushing the "Make your bed" meme a few years ago, and despite everything else I disagree with them on, this piece of advice actually helps I think.
I.e.: If you stuggle with motivation and diligence, then start your day with a task that is small, low effort and achievable. Force yourself to get up and do it every day. Succeeding in one small task can provide the encouragement and motivation to tackle larger tasks afterwards. So the idea is that one small success will cascade into larger ones throughout the day.
If you are unsure that you can trigger a cascade, maybe some varient on this idea can help some people. Perhaps instead of hoping one small success will snowball into larger ones by the end of the day, try tackling a larger challenge right off the bat of a small success. Then succeed or not at that greater challenge, after a time, go and succeed at a different small task, and then either return to tackle that larger task again or try a different larger challenge, and then another small task to succed in, and then the larger task again and so on. Constantly give yourself those boosts in motivation from small successes.
Some people worry that by succeeding in small tasks and not larger ones, you may be wasting your time and not achieve much. However, I think at the very least and even if you fail all of the larger tasks you try to tackle, you are achieving a small level of productivity as opposed to none if you didn't even try to begin with. Moreover, after a while you will have established a new baseline level of productivity for yourself that includes those small tasks as habit, without you having to expend any motivation to even do them, meaning that you should be able to increase productivity over time if you assign yourself new "small" tasks to succeed in - which would actually be larger tasks than the ones you initially began with.
TLDR: Basically just choose something small and definitely achievable to do every day and do it. Starting something is the hard part, but once you jump that hurdle, you should be able to climb higher.