No, you do not have to pray to the saints to get into heaven.
CCC 169: Salvation comes from God alone
(assuming your friend equates salvation with a sure ticket into heaven)
CCC 517: Christ’s whole life is a mystery of redemption. Redemption comes to us above all through the blood of his cross, but this mystery is a work throughout Christ’s entire life
(what follows is a listing of events from Our Lord’s life, but nothing mentioned about praying to saints)
CCC 1023: Those who die in God’s grace and friendship and are perfectly purified live for ever with Christ
(nothing about having to pray to God’s other friends to be one of His friends)
It’s like my husband loves pointing out to me: You can be a devoted Catholic and never once pray the Rosary (I think he’s just lazy

).
That said, I can’t imagine why anyone would have this amazing resource of saintly intercession, and not use it.
It’s like having a big fat jewlery box full of priceless gems, and not putting some of them on, occasionally.
Cheers,
Cari