The different parameters you can set up on this sites are:
Automatically assign members this role: Select the role that you want to bot to auto assign (only one role can be auto assigned).
Minutes of membership required for role: Requires that a member must be on the server for
x minutes before assigning the role.
Require one of these roles to be present on the member: If a person does not have one of the following roles on them they will not be given a role.
Ignore people with the following roles: If a person has one of the following roles on them they will not be given a role.
Only assign role when they join, do not give it back if it's removed from them afterwards: Only assign the role to them once when they joined. If they lose the role sometime after, the bot will not give it back to them.