Let's break it down step by step.
1. Your set up, you are holding the ball a bit low, unless you are trying to throw the ball slow, hold it a bit higher. Elbow height should be your medium setting, ball higher than your elbow for faster speed, lower for slower. I would also like to see your head over your right foot just a pinch more so the ball is between your head and your right foot.
2. First step looks pretty good, I can't see your feet in the shot, so I will assume your foot started straight toward your target.
3. Second step, the ball should have started forward with your left hand taking the weight of the ball forward and slightly upward. Your ball is already leaking off to the right before you have even started it.
4. Third step the ball has just started and a foot off to the right of where it should be. Keep that elbow in tight to your body. If you look, the ball is not swinging, you are pulling it. This usually indicates a bad ball fit to where you have to squeeze the ball to hang onto it, you should never have to squeeze the ball to hang onto it, see your Pro Shop
if this is the case. The ball should be behind you in your third step just past your right hip. This step goes off to the left, my guess is to allow the ball to pass your right hip. Starting the ball a step earlier will solve this I think.
5. 4th step, the ball is still going back, it should be at the top of the back swing when the right foot compresses. The right foot is now diving back to the right to make up for the left foot stepping off to the left on the previous shot, again starting the ball with the first right foot step should solve this. The ball should be dead in line with your head and the target, you can see that the entire ball and then some is to the left of your head. Again, letting the ball swing your arm nice and easy and starting it with your right foot should solve this.
6. The slide is way back to the right, the ball is so far out to the right that you are having to pull it back to hit your target. It went from way left at the top of the back swing to way right on the way down to way left again at the release, you might want to fix this before you tear a rotator cuff. You are bending from the waist trying to force the ball out to the right, the key here is you are "TRYING" instead of just letting it happen. You are going to have to turn your inner control freak off if you want to get ahead in bowling.
Good luck, post another video when you are ready.