Hello,
It sounds like you have the Pro upgrade license, not the full Pro license. (If it is full Pro license, it is named either Windows 10 Pro, or Windows 11 Pro, not Windows 10/11 Pro).
Because it is upgrade license, you won't have the key. It is digital only.
To use it on your new laptop, you need to make sure home edition is already installed and activated first.
Then do the following:
You can go to Settings > System > Activation > Change product key
Disconnect internet, and disable any third party antivirus, key in the generic key instead: VK7JG-NPHTM-C97JM-9MPGT-3V66T
That should get you to Pro. Once restarted, you can connect back to the internet, sign into your Microsoft account. Continue with the following:
go to Settings > System > Activation, run the troubleshooter, choose the hardware change option. When it asks you where it is installed on right now, you should choose the old device name. Then click on Activate button. And on the next screen when it asks you where to transfer it to, choose your new device name. See if that does the trick.