If you need to set the pickup point on the created order, you can do it by going to order detail, clicking on More actions, and Choosing pickup points. The order needs to have a shipping method that requires pickup point selection. You can also change the pickup point as many times as you need.
Steps
Go to Shopify Orders
Open specific order that has shipping method requiring pickup points
Click More actions
Click Choose pickup points
Select the pickup point on the map