Bonjour Dyrce !
"Nous t'avons rendu visite il y a une semaine."
Literally : "We you gave a visit a week ago."
t' = you as an indirect object -> We gave the visit to you.
rendre visite à [quelqu'un] = to visit [someone]
See the related lesson : https://french.kwiziq.com/revision/grammar/visiter-versus-rendre-visite-a-visiting-places-versus-visiting-people
il y a + [duration] which is the subject of this lesson.
I hope that's helpful!
Bonne journée !
