Purchase: Purchase Workflows: Receiving Products
Purpose
Whenever a purchase order is confirmed, Odoo generates an operation type called a receipt. This document will cover how to receive products from a Purchase Order in the Purchase app of Odoo 13.
Process
To get started, navigate to the Purchase app.
Receive Products
Go to ORDERS > PURCHASE ORDERS. Here you can see there are some outstanding purchase orders. Select a purchase order from the list.
If the PO is ready to do so, you'll see the RECEIVE PRODUCTS button. Click this button to continue. 
Good to Know!
Receipt Smart Button
This smart button indicates that there is one or more receipt records. Clicking this button will either display completed receipts, or allow you to start the receipt process. If there us more than one receipt, that will be show in a list view.
Clicking the Receive Products button opens a new Inbound Transfer record. You'll have two options on how to proceed.
Option 1: Full Receipt
If all the products are being received, click VALIDATE.
The Immediate Transfer? window will appear stating "You have not recorded done quantities yet, by clicking on apply and Odoo will process all the quantities."
Click APPLY to proceed with receiving all products.
Option 2: Partial Receipt
If a different quantity is received than what was ordered, you would need to manually enter the amount. To do so, first click EDIT.
Under the Detailed Operations tab, click in the fields directly beneath the Done column and manually adjust the quantity(ies) received. For the purpose of this walkthrough, enter fewer than the number ordered for at least one product. When you're done, click Save, then click Validate to record the inbound transfer.
Because the demand does not match the Done, you'll see the following modal window.
The option to accept the order for what was received can be performed by clicking NO BACKORDER. In the instance where you only receive a partial order, Odoo gives you the option to create a backorder to later receive the products needed to fully complete the original demand.
We want to recieve the remaining items in the future, so let's click CREATE BACKORDER. This returns us to the inbound transfer.
Under the Operations tab, you'll now see the Demand has been adusted to match the Done quantities.
Next, use the breadcrumbs to navigate back to the originating Purchase Order.
Follow the steps previous to recieve the remaining quantities.
Good to Know!
Receiving More than Ordered
You can also manually enter Done quantities that are more than what was ordered. In doing so, you'll see the following modal window.
If the quantities are correct, click Confirm. If you've not yet created a bill, a new bill will reflect the actual received quantity rather than the quantity ordered.