The meanin of "You got it" said by an MC to a performer who is about to do something on a stage When an MC on a stage says "You got it" to a performer who is about to do something on a stage, what does "You got it" mean?

"You bet!" in a reply from restraunt staff to customers saying "thank you" upon leaving. Hi, everyone! While I lived in U.S. and went to restaurants there, upon leaving, I would say "thank you" or "I enjoyed a lot” or something like that. Staff would often reply “You bet!” or "You betcha!" I don’t still understand why they say this and its connotation. I appreciate your input on this.