Let’s jump to the most basic knowledge about chess that you can teach your kid as a beginner guide to chess. The difference between check and checkmate is a part of this basic knowledge. It is a very important lesson in chess to figure out if the king in check or checkmate.
The most basic answer to this question is that you need to ask yourself that according to its position can the king use CPR meaning Capture, Protect, Runaway to get safe.
If the king can save itself that means that it is the check, however, if the king cannot save itself in this situation that it is checkmate. When its checkmate, it means game over.
To completely understand this and to learn how to play chess you will need to practice with a few different positions.