Customer leads

You need an additional app to do so (e.g CRM app)

Welcome to the QuickBooks Community, IPND!

I agree with Fiat Lux - ASIA about finding an app to track your leads. Just click the Apps menu on the left-hand side in QuickBooks and search for something like customer leads or leads to find one. You can also submit a feature request to include this in future updates.
 

On the other hand, know that we have references for Sales and Customers should you need them in the future.

You can always go back to this thread if you have any other questions about QBO. Take care and enjoy your day!