the prince decided to banish(exiled) romeo from verona and if he was ever found in verona he would end up dead.
He tells Romeo that he could have received the punishment of death....
Punishment of banishment
Mercutio is the one who decides to fight Tybalt.
Saradomin (fictional RuneScape god) warned him of the quest ahead of him.
Mercutio decides to defend Romeo's honor by fighting Tybalt in his place. This leads to a tragic turn of events that ultimately results in Mercutio's death and Romeo's banishment.
The apothecary in "Romeo and Juliet" received a death sentence for selling poison to Romeo.
death
Friar Lawrence feels that a punishment is good when they are in harm and when Romeo is missing Juliet, that is a very good punishment.
Romeo gets banished from Verona
Sure. There are other possibilities for a fair punishment.
he decides to get a potion for suicide
The prince banishes Romeo from Verona because of his role in Tybalt's death. This punishment is surprising because the prince had previously shown leniency towards Romeo and because banishment is considered a harsh penalty for a young man in love.