Admin can login in Odoo database and go to 'User Roles' modules. After this, click on "Create the New Role" button, enter the name, and define the various access rights for the groups. Go to Add user for the role then click on "Save" Button. You can go to the user tab here to create a new user by clicking on "Create" button and checking the assigned roles of each user.
Odoo Security roles to users define how different individuals like salespeople can access various types of documents.
