Depends. Warn first. "HOT! Touch it. Ouch!" Then if child tries, you give them a good prompt. "HOT! Don't touch! Ouch!"

Now, controversially, some parents will then let the child have free will and find out what it means to put your hand in the flame. Yes, there will be blister burns. But that will be a lesson learned for life.

I once touched a soldiering iron. I learned to be careful of soldiering irons for life. 🤭