i formated my laptop but now i dont have ms office product key

Hello, good day and thanks for your question. I understand that you formatted your laptop and you are in the process of reinstalling Office again.
May I check and confirm if this is pre-installed on your device or this is a separate purchase that you made?

Also, is this Office 2021 or Office 2024 or a Microsoft 365 subscription?

In most cases, you should be able to reinstall Office via your associated account at https://account.microsoft.com/services .