Camila Cabello is inviting one lucky fan to spend a day on set with her and make an appearance in her next music video as part of the All-In Challenge."I'm offering a day on set of my next music video when social distancing is over," she said in a clip shared on social media Saturday evening (May 2). "You will make a cameo in the music video, you will learn choreography with me, I'll teach you all the moves -- well, my choreographer will teach us the moves."The winner will get a roundtrip domestic flight, a one-night hotel stay and the on-set experience with Cabello.The opportunity is part of Philadelphia 76ers co-owner Michael Rubin's All-In Challenge, in which celebrities -- including Madonna, Drake, Justin Bieber and many more -- are.