OH this is so perfect bc i am literally watching a netflix show right now with a secret royal trope (it's called prince of peoria and is a super fun family sitcom, go watch it).
SO freddy is like a prince who just wants to live a normal life and with the help of his bodyguard victor, manage to sneak away and book a flight to the US. it's summertime so school is out and freddy’s watched tons of movies about the american camp experience so he wants to go. victor poses as his dad and signs him up for a sleepaway camp and also gets a job as an assistant counselor so he can keep an eye on the prince.
freddy ends up as bunkmates with billy who's kinda confused by how properly freddy speaks and the way he freaks out over every animal and bug he sees at camp, almost like he's never been outside before. he still stays by his side to help show him the ropes, which is basically like teaching freddy everything from swimming to rowing to even just, like, how to eat burgers and hot dogs. freddy even ends up twisting his ankle while playing soccer and it's the most alive he's felt in years.
yeah billy probably ends up finding out the truth about freddy bc the king orders a mass search for his son and it's all over the news and while there really isn't wifi or many tvs at camp, there's one in the mess hall and billy watches it while freddy’s back at the bunk, resting his ankle, and they display a picture of freddy and billy’s just like shit.
it's also slow burn and mutual pining bc duh but they're both too scared to say anything, like freddy just knows he likes being around billy and billy gets really anxious and sad when he realizes freddy has to leave and yeah.
freddy does get dragged back to his home country and only returns to surprise billy on the last day of camp bc his mother noticed how sad he was and freddy admitted to liking a boy at camp so his mom begs his dad to let him go back, since maybe she was a commoner and his father fought for them to be together as kids, so they fly him back and he surprises billy and they kiss and yeah. maybe freddy and victor move to the US until freddy turns 18, when he legally has to take on his princely duties and get married.
also the rest of the shazamily are fellow campers and friends with the boys. rosa is a counselor for the girls and victor becomes smitten with her and they get their happily ever after too bc victor gets to keep dating her when he and freddy move to the states. (but eventually they get married and he quits his royal job and maybe freddy steps down as prince so he can stay in the US with billy forever and never have to worry about royal duties again.)