It's a really good squat to a box, but it is not a box squat.
You're going to have to push your hips further back. In fact, you'll push your hips so far back that your knees will either be vertically in line with your heels or even further back.
You'll have to push your hips back the entire time you're descending onto the box.
This will leave your torso more leaned over than you're probably used to.
This may or may not be a good thing depending on your squat style and weaknesses.
To keep yourself from getting too bent over, you'll really have to push your knees out hard and use a very wide stance.
You are landing on the box very softly. That's good!
I always cringe when I see people do them incorrectly and just plop on the box and watch their torso and back collapse and rock back forward for momentum to get off the box.
But you need to relax your hip flexors when you're on the box.
To get this down, just do like you would for a box squat with barbell, except with just your bodyweight. When you sit on the box lift your knees up. When this is done, all of your weight is on the box. This is what should happen in a regular box squat. This is something I learned from a Clint Darden video and worked great for me.
All of your of weight will be on the box, but you shouldn't lift your knees up for the actual lift. That's just to understand the concept. Keep in mind that when your hip flexors are relaxed, your torso will tilt to be more upright and the bar will go back a little but when you initiate the ascent the bar will be over your midfoot again if done properly.
That's at least part of why you relax your hips flexors, so all of your weight is on the box. It'll make it much more difficult to get off the box because it will be closer to being a deadweight. You're torso and back has to remain very tight when this happens. This is very important for both training effect and safety.
When you try to get back up, you do this by contracting your hamstrings from both ends (like a glute ham raise or swiss ball leg curl) and squeezing your glutes as hard as you can. Because of how far back your knees are, there will be almost zero knee extension. Think of the box squat as a big hip abduction with hip extension.
By doing these things, you get all of the benefits of a box squat.
Now don't get me wrong, I don't have a hardon for box squats, but I do find them very useful as one of the tools I use to build my squat and deadlift.
For me personally, they're best for developing that 'pop' when getting out of the hole by teaching me how to stretch and load my hams and hips when descending and transferring that energy to powering out of the hole so I bounce back out from the stretch reflex. But this only works if I include regular squat work with it.
For improved positioning and feeling more comfortable with my squat and learning how to recruit my quads better, I prefer paused squats. But I don't find them as useful for power out of the hole.
One more thing, lose the Oly shoes. They make it a lot harder to sit as far back as you need to. I personally prefer oly shoes for free squatting, but I hate them for box squatting.