Emails sent by the school's Comms package are outbound only, there is no inbox to receive replies. In the text of the email it will say:
"This email was sent on behalf of Test School (your school name) via ScholarPack MIS. Please reply to firstname.lastname@example.org (the School Contact Email address in your School Details table)"
To check the email address that appears here, go to Admin > Config > Core Setup > School, or click on the school name at the top right of your ScholarPack screen.
If a student's contact clicks on Reply to the email, it will not be received by the school. Instead they will need to email directly the email address given in the email.