Hello, I published my game and it requires a serial key to unlock the game.

I thought that I would receive the contact of the buyer so I could send to it to him.

How can I do it?

You can find a list of buyers with their e-mails at the bottom of the game's analytics page.

You could also skip the whole emailing process by uploading the keys to Itch. From your game's edit page go to Distribute -> External keys and select the key type "other". You might want to add a line to the download instructions explaining to players that they need to claim the key.

Great! Thank you both.