1) What does each character want?
2) How far are they willing to go to get it?
#1 gives each character their "driver" for the story. Whatever it is needs to be something important. It can't be something minor. My driver for the first half of my life was to write and sell a book. That was always behind all my major decisions. I did not share that with everyone, either. Expect your characters to be equally shy.
If you don't know the driver for every character, your story will meander because no one is willing to take the lead in the action. It winds up with characters who are reactive, not active.
Young Skywalker wants to be a pilot and fight the Empire. Two escaped droids -- one on a rescue mission -- make that happen.
Rick just wants to run his nightclub and doesn't stick his neck out for anyone -- until the love of his life who broke his heart turns up out of the blue.
Agent Clarice Starling is willing to talk to the sickest, most dangerous, most intelligent serial killer if it helps her to stop another serial killer.
Lucifer Morningstar, fed up with his job in hell and teaming with daddy-issues, runs off to Los Angeles for a vacation. He keeps getting sidetracked by an attractive detective who doesn't fall for his BS.
Now--write something like the above for your major characters. It may clarify things for your story.
As far as scenes are concerned: each one needs a beginning, middle, and end -- and pushes the plot forward in some way.
If each chapter covers two plot points, your pacing will perk up.
You may want to print this and stick it up over your desk. I doubt you'll want to repeat it 200 times for a single book, but it might help!
https://johnaugust.com/2013/writing-a-scene-in-11-steps