that filter eh hem...kinda sucks. Go out and pay 30-40 bucks for a better HOB
or possibly a canister or something. If your just beginning you shouldn't just rely on live rock and a skimmer to do all the filtration, because frankly, you probably won't have much success. I hate the fact of people having no filters on they're tanks, but some of the more experienced people have had reefs without filtration (hobs, canisters, and the like) and had great success somehow, but a beginner probably wouldn't have the best of luck with it.
Will you need live rock? Flat out no but it's probably a very good decision to at least get a few pounds to help out with decoration and a great biological filter.
Is the lighting enough? Yes if your not getting into the reefs. If later on you want a few things certain types of macro and mushroom corals usually do good under lower lights, mushrooms actually will die under high lighting. If you do want macro do your research first. SOem CANNOt, and I say cannot with an absolute, be kept under low lighting. A lot will go sexual (turn white and die) if under low lighting.
Protein skimmer a necessity? NO. It's not a necessity but it's one of the greatest add-ons you can get. Not only does it oxygenate your water but takes out phosphates, dissolved organics, and numerous other unwanted materials. Go for ones like the coralife needle-wheel skimmer or the hang on back nautilus. Watch out for the hang in tanks ones (plastic tubes with a wooden stone) and the seaclones.
Substrate- With what you have it's ok. I personally hat eplaysand but it's okay to use in saltwater tnaks. If you can get crushed coral cheap or in small amounts get soem and sprinkle in the back to help out with buffering the water a bit.
tanks aren't as much as reefs but they are still usually expensive and not only require the big equipment but all the little things that need to be bought. DO your research beforehand and make sure you have a thorough understanding of saltwater before you try, I guarantee it'll be easier in the long run!
Well, i'm getting a typing cramp lol so i'll leave it at that for right now.