Hey there!
Thanks for submitting your form check.
I see a couple of issues that could be slowing your progress putting weight on the bar.
1) Stance- You are taking too wide of a stance for your build. This stance is making it difficult for your to get your knees out and keep your knees out and it is cutting off your depth a bit. Narrow your stance by about 2 inches on each foot. Keep the same toe out angle- just bring the stance in.
2) Bar Placement- You definitely have the bar too high on your back. Remember that the bar should be placed- UNDER the spine of the scapula, not over it. The shelve that the bar rests on is made of the meat of your upper back muscles. Right now you are over it and trying to rest the bar on your traps.
Spine of Scapula.jpg
Here is a video I made- describing how you can better put the bar on your back. If you find you have a difficult time getting into this position- you may need to stretch.
YouTube
3) Keep your back tight! - Getting the bar in the right place is a start- but you also need to get your back into proper extension.
Here is a great article on the subject from our archives:
Identifying and Correcting Thoracic Spinal Flexion in the Squat | Bill Hannon
I would also recommend holding off on using a belt until you are sure you are keeping your back in very good extension. Take some weight off the bar if you have to. It is difficult to learn to keep your upper back tight if the weight is already heavy for you. Learn how to do it well and THEN add the belt.
Keep up the good work!