Hello, I have a question, my son is 1 year and 10 months old and he of…

Hello, I have a question, my son is 1 year and 10 months old and he often touches his genitals. He wears underwear without diapers and just sticks his hand in there, does it when he wants to write or just like that, very often. Can you tell me what this is from? How should I react? Could it be nerves on him or something else?