It's been a rough learning process so far :') my main issue is that I like to play on the go using apps or mobile spreadsheets and the book relies a lot on the printed sheets. They are way more organized than the book which has a number of issues (12 actions are not listed nor mentioned in actions chapter but after character creation, common equipment is given after character reaction chapter but the load somewhere in the middle of it, etc). Once you have done a character / band creation end-to-end it becomes much clearer.

I suggest to listen (or watch, but listening is enough) to Blades in the Dark by Oxventure. At least the first 15 to 20min or the first episode. You will have a good illustration of the engagement role and how players select their skill.

I GM Blades since 10 sessions if you have questions. Even if it would be out of topic.

Edit: Oxventure don't follow all the rules which present a simplified and more accessible way to play BitD to me.