Can anyone help me?
You dont step to the target. You are stepping and planting more towards the 3rd base dugout then you are towards the plate. You are throwing across your body to compensate.
Your fingers are far too separated for a “4-seam” fastball. Your finger placement is more in line to a splitter.
You are dipping… going up and down and not driving forward.
You do wait for core rotation until foot plant, that is good, but your glove is dropping the entire time verses staying up and pulling your body to it. You also are starting forward with your arm as your body rotates which is why you are throwing the ball before your body is facing the target. Your arm never gets to a “cocked and ready” type of position but it starts rotating with your core thus you tend to “catapult” the ball - for a lack of a better term.
Lots to work on and stick with it. You could use some professional coaching who can quickly point out these issues (and others) and give you some guidance on how to fix by doing various drills.
You are opening your left shoulder and hips before foot strike due to the poor stride direction and lack of glove side control.
You are virtually eliminating your external rotation. You will get nothing on the ball for velocity.
I’d work on striding forward and keeping your shoulders on the target line. Try to keep your glove out in front of you and pull your chest to the glove.