Can I buy gift for the person which does'nt have the account on gog yet.

Yes, but they can only redeem it with the account.

Yes,just hang on to it.

Thank you

More specificially, just enter your own email where it says "Person You Want to Gift To" or whatnot.

Then you'll have a code both emailed to you AND in your account (it's located under your name at the top middle of the screen - in the drop down menu you'll see "Orders and Settings").

Then you can just give them that code when they get an account. But they WILL need an account to redeem it.