No one will give you a product key. If you bought a computer with Windows 11 installed it should either have a licence from the manufacturer or you need to buy one.
To check if a licence is embedded in the bios open Terminal (Admin) and enter
wmic path SoftwareLicensingService get OA3xOriginalProductKey [press return] If there is a licence from the manufacturer the command will display a 25 character product key.
What is the result.