Can I add a custom field to a bill to track that customised fields' data entry

I'd be happy to join you here and answer your question about customized fields, nazbin786.

QuickBooks Online lets you customize sales forms to add more details before sending them to your customers. You can take a look at this article for more details: Customise Invoices, Estimates, and Sales receipts in QuickBooks Online.

However, the same option is not available for vendor or supplier transactions such as bills and bill payments. You'll want to use the Memo section of the bill to indicate the kilo-liters. 

I also recommend sending feedback about this to our engineers about being able to customize bills and add more bills. Here's how to send in your product suggestions or feedback in QBO: 

1. Go to the Gear icon and select Feedback.
2. Type in your feedback and suggestions about customizing bills in QBO.
3. Click Next to submit them.

Aside from that, there are also third-party apps that can help you customize bills. Here's how to look for accredited apps:

1. Go to the Apps menu and proceed to the Find Apps tab.
2. Click the drop-down list for Browse category and select a category.
3. Choose an app and click on it to view more details about it.

Let me know if that answers your question about adding customized fields to bills. You can also get back here anytime you need help from us.