If the question you think you’re asking yourself is, “how can I begin now?” but it really feels like, “how much shame should I feel for not having done this already?” — don’t despair.
The dissonance you detect between what you think and what you feel is a part of the human experience, and how you deal with this dissonance is up to you.
I’m not being glib, I literally mean that you can decide how to act rather than acting reflexively. If you’re ready to be the kind of person who sticks with tasks until they’re done, you’re allowed.
Sounds like freedom to me.