- Are you fell on your head when you were kid?
- Have you fallen on your head when you were kid?
- Did you fell on your head when you were kid?
Which one is correct to say.
Your event took place in the past: “when you were a kid”.
For this reason your first option cannot go as are refers to a present event.
The second option doesn’t go too as the event should have ended in the past without any implication to further time sequences.
Your last example is correct if you use the auxiliary do in the past, did+bare infinitive fall:
Did you fall on your head when you were a kid?
Just add an 'a' before the kid and the third one is correct
The second one is wrong because 'have' refers to recent past. For distant past we use 'had'. So the right question would be " Had you fallen on your head when you were a kid?
The first one is wrong , because questions starting with 'Are' refer to the present. 'Fell' is the second form of the verb 'fall' and addresses past.