Hello there, @Yana0505.
I hear you and realize the importance of being able to add custom fields on the bill template in QuickBooks Online. Having this feature would be convenient for you and your business.
Please know that our developers are constantly working and considering new functions to be added to the system. This way, we will be able to meet our customers' needs and demands.
On the other hand, QuickBooks integrates with various third-party applications. You may check out our app site and look for the application that supports this functionality.
To stay in the loop with our news and updates including product road-maps, I encourage you to visit our QuickBooks Online Blog.
Lastly, I'm adding a link about viewing all your vendors transactions in QuickBooks Online, in case you need it in the future: How to view all transactions for a vendor.
Know that my doors are always open to help if there's anything else that you need. I'll make sure you're all set. Thanks for coming, and stay safe!
