How and why to prune mango trees - second pruning explained 

Thanks Abhayji will keep the music down in future. ☺️. I wud suggest you watch videos on how to prune mango trees and not saplings. As your trees are 4 y years old, I would not suggest hard pruning. Thinning the branches to open up the center and leave branches which go sideways . And gradually every year you can train the same way to achieve the short and spread out canopy shape.

Please identify my mango plant