To change a user’s role, Admins can go to Settings > Workspace Settings > Members.
In the Members list, look up the user you want to change the role for and click on Edit > Edit Role.
There you can change the person's role and click Save changes.
Only the Primary Contact has the rights to manage Admin users.
To add or remove a user as an Admin, please reach out to the Primary contact of your workspace. You can find out who it is in Settings Members.