Welcome to the PokeCommunity, Keviroo! You've join just the right place to get into ROM hacking, as we have loads of resources and people who can help you! You can find the ROM hacking section
here. Hopefully you can hop into Sun & Moon, those games were a huge step up from Gen 6 imo, you'd have loads of fun playing them. Feel free to shoot me a VM if you need anything, see ya around! :D