Why does my mesh not deform correctly when I move a bone?
This problem occurs due to your last bottom child bone. You can solve this in weight painting mode. You just select top bone of leg and you see no color with white / blue/ yellow / red to your right leg mesh. just try to select bottom bone of left leg and see right leg shoe has some white color. So remove that white color in weight painting mode. solve problem.
then in second image you can see different color circle. In this you can see painted and not painted mesh by selecting bone with same color. Now You can easily paint your mesh and remove painted mesh with just increase and decrease weight from 0 to 1 in left brush panel.