Yes, 78u.org can receive emails.
Yes, 78u.org seems to be a legitimate domain.
A record
139.99.135.8
MX records
mx0.mail.ovh.net
178.33.252.245
mx1.mail.ovh.net
188.165.36.237
mx2.mail.ovh.net
87.98.160.167
mx3.mail.ovh.net
91.121.53.175