Assign Access to the Channel Order App

Assign the COA User permission set to give team members access to the COA. This permission set lets users submit, edit, clone, and recall orders and view customer details. To view and configure service order credentials or import product data, users must also have the Customize Application permission.

User Permissions Needed
To assign a permission set:	Assign Permissions Sets

Log in to the org where the COA is installed.
From Setup, enter Users in the Quick Find box, then click Users.
Select a user.
In the Permission Set Assignments related list, click Edit Assignments.
Select the COA User permission set, and click Add.
Click Save.

ISVforce Guide

Assign Access to the Channel Order App