Narrow your stance a bit and get more bent over at the beginning.
I just turned 50. 6'1" and a fat 276 pounds. I stopped training back in April due to significant knee pain from a torn meniscus that happened in mid January. I believe that excessive knee side caused the injury. I only made it up to 210 pounds on my squat when I stopped training. I cancelled a planned knee surgery in June and finally feel good enough to train. I am starting completely over with light weights to focus on form to try to prevent re-injury. Here is the 3rd set at 125 pounds. Please let me know what to work on.
Narrow your stance a bit and get more bent over at the beginning.
it looks like you are setting the bar too high on your back. When you squat do you feel like the weight begins to go forward onto your toes instead of being balanced on the mid foot? If it does then try and drop the bar a little lower on your back.
Try it.
Here is my latest 3rd set from tonight. Video angle didn't capture my feet well, but I did narrow my stance a little. I struggle to balance getting my chest pointed down quicker with not breaking hips before knees instead of simultaneously.