Why can't you add a tag when reviewing a receipt, why do you have to create the bill or expense and then go back in to add it?

Hi usersuzanneflux, thanks for posting on the Community

Tags are a transaction-level feature meaning they can only be used on transactions such as expenses or bills. 

If you would like to share feedback with our Product Development team, please see the Settings wheel and then Feedback in QuickBooks. 

Thanks for reaching Intuit support. I'm just a post away if you have further questions.