You can set the user role and login option from your registration form settings. Please go to your Dashboard >> User registration >> edit the form you created >> Form Settings >> Choose the role and user login options according to your needs.
We are sure the registration plugin does not automatically approve users and set the administration role in default. Maybe your other third party is responsible for this, so we suggest you deactivate all the plugins and try user registration. If you find the same issue, please provide us with the user registration form link. We will look into it and get back to you accordingly.
Thanks @shresthauzwal it worked!