Idk what's average: English B2??

My interpretation is that OP is a non-native English speaker, and someone else used the word "exfoliate" in tandem with a joke

So now OP is trying to decide whether to roll with it and laugh, or search what "exfoliate" means

Exfoliate: To remove (a layer of bark or skin, for example) in flakes or scales; peel.

Source

In typical conversation, it means, to remove dead or dry skin by scrubbing