Simplify the following text for a Grade 11 native English-speaking person.
Original: Gambon made his professional stage dÃ but in the Gaiety Theatre , Dublin 's 1962 production of Othello , playing `` Second Gentleman '' , followed by a European tour .
Simplified: Gambon made his professional stage dÃ but in the Gate Theatre Dublin 's 1962 production of Othello , playing `` Second Gentleman '' , followed by a European tour .