I bought three rods and three reel's 2 medium fast and 1 medium heavy and 2/6.8.1 lews speed spools and 1/7.5.1 speed spool what line should I use for them an what backing if any

Mediums I would use 20-30lb braid. MH I would go up to 40 braid. Backing is up to you. I would want at least 150 yards of braid on each.

will they hold that much ? they say 120yards of 12lbs an I'm kinda new to getting the right equipment im just getting started in bass fishing real heavy. I always just bought whatever I liked to trout fish, catfish ,and fish walleye fish but never got good equipment

Buy some 14 lb mono to start with.  Trilene XL is a good line.  There is no need to over complicate things right now.  A good mono will get you fishing and won't cost a fortune if you backlash badly and have to cut some out.  Keep it simple.

mccoy copolymer

I've heard bout copolymer just never used it

i think youll like it. whether its mccoy or pline or yozuri hybrid they all work great its all i use except one setup with braid

Tim. What kind of cover are you fishing? If you use 20-30 the 150yards with a few layers of base backing should just about fill the spool. Ice learned keeping my spools filled on my casting reels allows for better distance since it takes less rotations of the spool to allow line to come of faster and smoother. Even in clear water I would use the braid with a flouro leader of your choice of lbs depending on clarity.

well our lakes don't have hardly any grass or weeds its alot of brush, stumps,and timber some evergreens growing up out the water and alot of rock beds,and cliff facings

I second the McCoy mean green copolymer

Unless fishing areas of sharp rock I would use the braid and flouro leader for the sensitivity. 150 yards of 20-30lb braid should fit into "most" casting reels.

Line has more to do with what you are throwing. I back with 30lb braid.