Thanks for joining the thread and providing detailed information, Spicey.

Let me convert the steps provided by my colleague GlinetteC to QuickBooks Desktop (QBDT). 

To turn on Purchase Order (P.O), you'll need to be the administrator. Here's how:

1. Go to the Edit menu at the top, and tap Preferences. 
2. In the left menu, click Items & Inventory. 
3. Tap the Company Preferences tab, put a checkmark in the Inventory and purchase orders are active checkbox.
4. Click OK. 

Once done, you can now receive a partial purchase order by following the steps below:

1. Create a purchase order. 
2. Record the items you received by creating a bill or create a check or credit card charge if you paid the items as soon as you received them. Make sure to edit the QTY column and enter the actual quantity received. 

After that, when you open the P.O, it will now show the actual quantity received in the RCV'D column. Then, when the items remaining is received, the P.O will show closed. 

In case you'd want to receive an inventory without a bill after entering a P.O, check out this article for a guide: Receive inventory.

Keep in touch if you have further questions. I’ll be around to assist further. Have a good day.