"Bye, Felicia" is a phrase that originated from a movie called "Friday" in the 90s. It's a way of dismissing someone or telling them to leave, usually because they're being annoying or unwanted.
Imagine you're playing with your toys and a friend comes over and starts messing with your things. You might say "Bye, Felicia!" to tell them to leave and stop being a bother. It's just a playful way of dismissing someone who's not welcome or causing trouble.