At the top is "au sommet" in French.
sur.
A cherry on top in French is - Cerise sur le gâteau.
"Come back" in French is translated as "revenir".
be right back
au sommet, au top niveau
You can say "Je serai de retour" in French.
Dernier etage.
elle reviendra
rembourser
This is how u say thank you for getting back in french:''Je vous remercie pour se remettre''.
In French, you would say "Bienvenue de retour à l'école."