1.Laisse-moi tranquille!(Leave me alone)
"Laisser" means to leave and "tranquille" means quiet, calm or peaceful.
Exemple : Arrête de m'embêter et laisse-moi tranquille! (Stop annoying me and leave me alone)
2. Va t'en! (Go away)
This is an informal expression meaning go away! or get lost!
Exemple : Va t'en! J'essaie de me concentrer. (Go away! I am trying to focus here)
3. Tu vas me lâcher, oui? (Leave me alone)
This is an informal expression. "Lâcher" means let go of something or someone.
Exemple: Tu vas me lâcher, oui? J'en ai assez de tes questions. (Leave me alone. I have enough of your questions)
4. Fiche-moi la paix! (Leave me alone)
This is an informal expression. "Ficher" or "foutre" is a slang verb and it has several meanings: to do, to give, to put etc... "La paix" means peace.
Exemple : Fiche-moi la paix! Je veux être seul maintenant. (Leave me alone! I want to be alone now)
5. Casse-toi! (F*** off)
This is an informal expression. "Se casser" in slang means to leave, take off.
Exemple : Casse-toi! Tu fais chier. (F*** off! You are so annoying)