You can control which collections appear in the collection filter on your order form. To do that, first, make sure your Product Restriction is set to Hide Collection From. If not, the below article can help you change the setting.
To hide a collection from specific customer groups:
- Go to the collection you want to hide and click the dropdown under Hide Collection From.
- Select a customer group from the drawer to hide the collection from,
No Customers— Everyone will see the collection on the order form dropdown filter
All Customers— No one will see the collection on the order form dropdown filter
Guest Users— Users who are not logged in will not see the collection in the dropdown
Customer Tags— Select a list of customer tags who will not see see the collection in the dropdown. Here's Shopify's guide on tagging customers.
- Click Save.
To show products too, follow the instructions in the article below,