Add a new Unit Name

Is there any option to add a new Unit Name or change the exist one?
How to make an full paid invoice without adding New Payment

Please don’t ask multiple questions in a single post. That reduces chances for answers for either.

To add a unit name, just enter it. Those originally there are just examples.

You can’t enter a paid invoice. Those are two distinct transactions. If a purchase is paid for at the time, you don’t need an invoice, just a receipt for a sale or a payment for a purchase.

Ok thank you, but how to enter a purchase invoice with receipt from a supplier

You don’t receive money from suppliers. You make payments to them.

Read the Guides:

Thank you very much,
And how to organize items by group?

You need to read the Guides generally. So far, all your questions would have been answered. Read this one:

I see, thanks

I have two group of books:
big books and small books, so how to group these tow groups in the Chart of Accounts under the Inventory on hand account?

This is a new question. Please start a new topic and be more specific. Before you do, read the Guide about custom control accounts.