Is it cheating if you don’t say check in chess?

Is it cheating if you don’t say check in chess? It is only necessary to say check or checkmate in a chess game if you are playing with your friends or family. If you are just teaching someone chess ( just like when I’m teaching my daughter chess) or you can say check after waiting for your opponent to move.

It is only necessary to say check or checkmate in a chess game if you are playing with your friends or family. If you are just teaching someone chess ( just like when I’m teaching my daughter chess) or you can say check after waiting for your opponent to move.