I’m having trouble with editing my Minecraft skins

hello, I’m having some trouble with the skins in Minecraft. I don’t know how to describe it, but I have a video showing what’s going on. And can you fix this

thank you

copy this link and look it up:

https://share.icloud.com/photos/0d5dKicDk4GzgnHgBGOUKRMCQ