These holes are designed by the manufacturer with the purpose of being used as a position to fix ladles, spoons, chopsticks, etc. while you are cooking and want to rest your hands to handle something. Very simple, you just need to insert the handles of the ladle, spoon, chopsticks, etc. into these holes. Hearing a hundred times is not as good as seeing once, below are illustrative images so we can visualize the function of the holes: