English Translation
We’ll bump them off!
I had no idea what the english idiom meant but apparently in this context it means to kill somebody essentially.
On Tatoeba it’s a translation from “Let’s give it all we’ve got.”
English Translation
Let’s give it all we’ve got.
Chat GPT translates it as “We will skin them alive“. When I have heard that phrase used in English, it means something like, “They don’t have a chance of winning“ or “We will beat them so badly“ or “We are going to pound them into the ground“ implying some helplessness on the part of the victim to stop it.
Which, conveniently, is also what the French expression “faire la peau” means. 
I think that’s pretty much all there is to it. I guess it may be considered kind of old-fashioned.
There is also “vouloir la peau de quelqu’un” (to want somebody’s skin), which depending on context can mean:
- wanting to kill them
- wanting to hurt someone, socially or professionally (maybe you want their job), although with that meaning, “vouloir la tête de quelqu’un” (to want somebody’s head) may be more common.