Can i find when my account was created ?

Kind of a round about way, but assuming you played the first day, you can check your match history and filter it for your first champ played (if you remember who it was) and game type (assuming you started with bots). That should narrow the results, so you don't have to scroll down too far.

You might be able to send a support ticket and ask them, given that you can answer most of their extensive questions they usually give when anyone has a question about an account.

just check ur email and see when u got the email for creating your acc