I haven't watched any of the shows she mentioned. No idea what to do!
She gets invited for a Christmas party and the Santa there gives her a gift. When she opens the gift, she finds the autographs of her favorite pair (maybe Arnav and Khushi). After seeing this, she goes to thank the Santa. When she was searching for the Santa, she meets Arnav on the way and he takes her to Santa and the Santa turned out to be Khushi. Later she spends time with them and in the end, her friends come and they all cut the cake.