goofball

US /ˈɡuːf.bɑːl/
UK /ˈɡuːf.bɑːl/
1.

a person who is silly in a way that is funny, often intentionally:

:
He plays the role as a lovable goofball.
1.

silly in a way that is funny, often intentionally:

:
He made everyone laugh with his goofball antics.