I can definitely help you find your license number. If you have QuickBooks Desktop, you can locate your license number by opening your QuickBooks and pressing the F2 key. That will open a Product & Information window.
QuickBooks Online accounts don't have a license number, they have a Company ID(CoID). You’ll find your CoID on your Billing & Subscription page.
Click the Gear icon.
Choose Account & Settings.
Select Billing & Subscription on the left. The Company ID will be displayed at the top.
I’m here to help you with any other questions you may have. Please feel free to comment below!