Ok. What you want to do is when you are at home, just practice your footing. Make sure that first step is small no matter what you do. Eventually, it will wort into your muscle memory and it will be something that you just do without thinking about.
Secondly, you might want to consider taking a step back on the approach. You stat with your heals on the second set of dots. Maybe put the tips of your toes on that set of dots instead. That should give you about a extra almost foot of slide before the foul line, allowing you to get down into the shot better.
As for getting that knee bend, start by just focusing on keeping your shoulders up. Once you are able to keep your shoulders up and not bending forward at the waist, you and integrate that knee bend. You can do that by on your last step (slide step) going down as if you are about to sit into a chair. When you go to sit in a chair you let your knees bend until you hit the char, and same idea goes here (you just dont go all way way down)
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