A purchase order is how you restock from a vendor — draft it, send it, receive it when the truck shows up.
In the POS mode, open the Orders left tab — that's where every PO lives.
The top-tab strip on Orders is the PO lifecycle, left to right. Each tab is a stage a PO moves through.

New — the empty builder; start a fresh PO here.Drafts — in-progress POs saved but not yet submitted to the vendor.Ordered — sent to the vendor, waiting on the truck.Received — stock is in; invoice details still to record.Vouchered — invoice recorded; ready to be paid. Kicks the PO over to your accounting side. See Vendor invoices for what the invoice form is doing.Paid — marked paid.Voided — canceled before completion.Special order products — products on an in-flight PO that were triggered by a Special order on a sale. See Special orders.Each tab shows a live count of POs in that state.
Open the New top tab (or click Orders in the left sidebar — it lands you here by default). You'll see the PO transaction-builder: Order from on the left, product search in the middle, totals on the right, and the action cluster at the bottom.

The Order from dropdown is the only required field to get started. Pick a vendor and the builder unlocks — side-panel fields appear, product search becomes active, and the Order button on the bottom right lights up once the cart has a line.
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Rundoo doesn't flag missing fields when you click Order or Save draft on an empty PO — the button just does nothing. If nothing happens when you click, double-check you've picked a vendor and added at least one product.
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