The word "promote" is a verb, which means to help something grow, improve, or become more successful. It can also mean to make people aware of something, like a product or an idea, so they will want to buy it or support it.
In Games: In games like chess or checkers, to "promote" means to move a piece to a special place on the board, where it can become more powerful. For example, in chess, when a pawn reaches the opposite side of the board, it can be changed into a queen or another piece.
In Work: In a job, when someone is "promoted," they move to a higher position with more responsibilities and often more pay. For example, if you work hard, your boss might give you a promotion to a manager.
In Advertising: To "promote" something also means to advertise or sell it. For example, a company might promote a new phone by showing ads on TV.