Other questions

Pleased to have you here, @Katipai.

I'd be delighted to help walk you through on how to enter a line item on your invoice and bill in QuickBooks Online.

When adding a line item on an invoice or bill, you can enter it one by one. However, if you need to add or change the rate of the line item, yes, you can add or subtrct on the same cell. But it will not automatically create a new line item. 

If you're referring to putting a sub-line item under a specific item to indicate a group or packages, you can utilize our QuickBooks Online Bundle feature.

You may check the video below for reference:

Looking forward to seeing your post here in the Community if you have other questions about creating an invoice and bill in QuickBooks Online. I'm always here to answer your inquiries.