Didn’t anybody read the crawl? 😉
Seriously, it was a lot easier to figure out than what the heck blockading Naboo and forcing the Queen to sign something was all about.
And Rey probably had some rudimentary training in the Force as a toddler she barely remembers until confronted by Kylo Ren. Why else would she be abandoned on a sithhole planet, except to keep her safe until she was older?