how do i get a body like these girls?!

That depends. If ure geneticaly set up to be a "big girl" or mayb very thin then that is how u wil stay. Nothing u do can significatly change ur body type. u CAN make small changes though.
If ure close to this body type anyway then just exercise and do the same work outs they do.
But dont even try if ure a totaly different body type. Ul only set urself up for failure.

Good luck :)

just eat well as per time.........and do exercises daily..........then you can mentain good health as well as good physical body..........