First… Welcome! Pull up a chair and get ready to read a LOT of good info here…
Fem (short for feminized) can be either automatic flowering (autos), or photoperiod triggered plants (photos). Its basically a seed that was bred and lacking the male chromosome so you get all females and dont waste space on males if you arent breeding.
Auto vs Photo. Well, generally autos will be much shorter time to harvest, I’ve had some go from seed to harvest in 70 or so days… Photos can be in veg that long if you want, and some really long running strains can be in flowering well over 100-120 days.
Definitely wanna read up some more. Fems requiring less light? nope, never heard that. You do have a decent light though, you’d be surprised how well LEDs can compare to halides and HPS bulbs… Photos can give bigger yields, outside monsters can yield pounds… But autos can do pretty dang good for a 2 month grow… 250-300g from 4 plants in 2 months would be enough to keep most people I know stocked for the year LOL