In EasyBilling, you can create documents from existing documents using two different methods, depending on the scenario:

1. Creating a document from a different document type:
If you need to generate a document, such as an invoice, based on another type of document, like a quotation, you can utilize the “Generate From” button within the document.

Let’s take the example of generating an invoice from a quotation:

1. Start by creating a new invoice.
2. Within the Invoice window, locate and click the “Generate From” button at the top.
   
3. A document list will appear, allowing you to select the source quotation from which you want to load information.
   
4. After selecting the desired quotation, click the “Load to Document” button at the bottom. The information from the quotation will be loaded into the invoice document.

2. Creating a document from the same document type:
If you wish to duplicate an existing document as a new document, you can utilize the Copy and Paste feature in the document list.

1. In the document list, select the document you want to duplicate, then right-click on it.
2. From the popup menu, choose the “Copy” option. A brief notification message “Selected document is copied” will be displayed.
   
3. Next, right-click in the document list again, and select the “Paste” option from the popup menu.
   
4. The document will be duplicated with a new document number assigned.
   

By using these methods, you can efficiently create new documents from existing ones in EasyBilling.