His Royal Highness The Prince Charles, Prince of Wales was christened Charles Philip Arthur George.

The related link explains in detail his name and many titles.

Charles the First was born as Charles Philip Arthur George Mountbatten-Windsor. Some of the titles he had are: His Royal Highness The Duke of Rothesay, His Royal Highness The Prince of Wales, and His Royal Highness The Duke of Cornwall.

He is the Prince of Wales because he is the next in line to be King of the United Kingdom. "Prince of Wales" is one of his titles.

There ain't no such person. The Monarch's eldest son (currently prince Charles) is entitled PRINCE of Wales. He also has other titles, including Duke of Cornwall, which may be the source of your confusion. Prince Charles is the Prince of Wales.

No Prince William is not The Prince of Wales. That title is held by the eldest son of the reigning monarch. The reigning monarch is Queen Elizabeth II and her eldest son is Prince Charles, who is Prince of Wales.

Prince William is known as Prince William of Wales because his father is Prince Charles.

When Charles becomes King, then Prince William will become the Prince of Wales