You will have to retarget the animations and the anim bp (or re-add everything in the anim bp) -> https://docs.unrealengine/latest/INT/Engine/Animation/RetargetingDifferentSkeletons/index.html
I would recommend you to take a look at this tutorial so that you learn the basics of characters + animations: 
Btw, I moved your thread -> you will get a faster answer in the other sections 