*There is 1 WordPress user Role used in our theme”Subscriber”. “Agents, Agencies, Developers or Users” are different types of the same user role. More here 

If you wish that an agent can manage his properties from front-end dashboard, create the agent from front end via the registration form and select Agent from the drop-down

Sync manually a registered user with a published agent post

Still, if you wish to add them manually you need to follow the below steps:

1. Create the user account

Go to admin-Users – Add New.   The user needs to have subscriber level

2. Create Agent Account

Add the same email address

3. Add the User Id to Agent account

4. Add agent ID in user acccount