Click on the Projects tab at the top => Select the project in which you would like to add user => Click on the User tab.
Click on the "+Add" button
Select the User from the dropdown=> Select the role of the User
If you want to allow permission for authentication and location then enable the toggle button and vice versa
Enable the toggle button for Web Access and Instruction Access as per the requirement, =>Select the Checklist => select the RFI user (if there is a RFI process)
Click on the ADD button