What’s the correct form/esecution of
1)Depth Jump"classic"
2)Depth Jump with knees bent at the to fix angle (high catch or mid or low)
3)Altitude landings?
I’ll leave this one to Chris T. 
What is important is that the athlete should step out and land away from the box approximately the same as the height of the box. So if the box is 30 inches high one should land 30 inches away. As for execution, it depends on what the goal is - but generally the technique should be the same for coming off the box as it is without - IE. If one is landing in an athletic position make sure that ahtletic stance is identical to their “normal” athletic stance. If one is performing an immediate depth jump their technique should be roughly the same as their normal jump Common mistakes are shifting the center of gravity too far forward, stumbling forward etc.
Is for the sprint or player of the soccer or???