Im Going into the 7th gym and my Team needs training but idk where to go
My Team is
Go to Route 118-123 and fight lots of Kecleons or fight Golbats at Seafloor Cavern. They give lots of EXP.
Register as many numbers on the PokeNav as possible, and then walk in and out of as many routes as possible so they could rematch you( they'll be stronger as well)
Note that you'll mainly fight trainers on the route you walk into, like only Bird Keeper Robert wanting to rematch when you walk in and out of Route 120, not a someplace like Route 102(you'll fight Youngster Calvin if you go there)