How to enable role in the registration page?
You can let users choose their roles within the signup page. This will make it easier to explore the site without having to define their roles later on. You can view the roles on "yoursite.com/panel/roles".
To let users choose the role within the registration page, first, you need to create a new role. Click on "Add new". You will be redirected to a new page.
Give the role a name and click on the permissions you want the user to be permitted to. You can select more than one permissions by control-clicking them. Then, click on the checkbox in front of "Allow user to select this role on registration". This is what makes the option of selecting roles appear on the registration page. Then, click Submit.
Now, you can see the Member type dropdown selection option on the registration form.
Besides Member roles, you can also add custom additional fields on the signup form. To learn about this see "Adding custom field in the registration page".