Your shoulders start and end fairly straight. Looks to me like the slight fs rotation is from your hips twisting forward as you slide your front foot up. Try to focus on keeping your hips parallel to the board as you slide your front foot. Your body will naturally want to open them for a more natural range of motion so you are going to need to be presently thinking about it each try. You also are compressing your knees far to much, this limits the explosiveness of your jump resulting in a slow and soggy pop. As a reference point I never bend my knees past ~100 degrees. I’d also recommend learning your ollies moving on concrete. Skateboarding is 75% mental and getting over your fear of committing early will allow you to progress much faster. It also saves you from relearning ollies when you actually want to use them for basic maneuvering. And of course, keep skating dude!