In the monarchy, the queen presents the members of the royal family with royal titles to show their prominent peerages for those with high-ranking. As such member, Prince George was born with quite the title. He is still a little boy, and as he grows older, his title is going to change.
Title
He will be a king one day. For now, his title is His Royal Highness Prince George of Cambridge. When Prince William becomes Prince of Wales, Prince George will become His Royal Highness Prince George of Wales.
Prince George’s last name
In the royal family, if you have a title His or Her Royal Highness, you don’t need a last name. But, if they are required to use one, for example for school, Prince George can use Mountbatten-Windsor, the royal family’s last name, or Cambridge.
His full name
Prince George’s full name is George Alexander Louis. The name George is probably in honor of Queen Elizabeth II’s father, King George. However, when Prince William and Kate Middleton were deciding the name for him, they wrote several names on pieces of paper and laid them down on the floor. Their dog Lupo sniffed one of the pieces which had the name George written on it, and that is how they decided to name their firstborn George.
How will his title change
When Prince William becomes King of England, Prince George, as the male heir to the throne will receive the title Prince of Wales and the Duke of Cornwall, which belongs to the male heir.
Will he be a king?
He is third in the line for the throne, which means that he will probably become a king one day. If God forbid something happens to Prince Charles and Prince William before his 18th birthday, he will become the Kind of England, but Prince Harry will be his regent until he comes of age.
Source: www.cheatsheet.com