Hi,
By default there is no option to view this in the purchase order(hope the order specified is the purchase order). If you need to see the delivery status of the purchase order, you have to click the delivery smart button and check the status of the picking. If you need the same in the tree view of the purchase order, you can create a compute field and show the status.
In the odoo apps store there is some modules for the same, but those are paid modules, if interested have a look at it: Delivery status for sale and purchase
For the delivery status of the sale order there is a free module: Sale Delivery Status
Thanks