Your best bet would be to find a local fly shop to buy materials. They can help you select the right materials to get you started, and also can give you some tips on tying patterns. This time of year many shops or local chapters of Trout Unlimited and Federation of Fly Fishers will be giving beginning fly tying classes. This is by far the best way to go, you’ll learn a ton. You can find local chapters in your area here:
Council/Chapter Search | Trout Unlimited - Conserving coldwater fisheries
Locate a Club
Buying materials can be really confusing, as you’ve noticed. A good fly shop will guide you through this, and you can ask a ton of questions, examine the material to make sure it’s the right size etc.
Just to throw some ideas out there for you, for dry fly hackle, the Whiting 100 packs have great hackle, but you only get one size and one color for about 13-15 bucks. They’ll tie about 100 flies, using the long saddle feathers to tie several flies apiece. Instead of a 100 pack, you could get a Whiting Bronze ½ Saddle for about 28-30. A Whiting Bronze Saddle will generally have most of the feathers in 2 sizes with some bigger and some smaller. Most seem to run mainly 14-16, with some 12’s and 18’s and maybe a few 10’s. Saddles from other brands usually run in bigger sizes, with most feathers in a 2 or 3 range of sizes. A Bronze ½ neck should give you enough feathers to tie around 250 flies. Because the ½ saddle is cut length wise, you’ll get a full range of sizes. (A ¼ Saddle is cut lengthwise and across its width, and you’ll end up with a more limited range of sizes either bigger or smaller because of the way feathers grow on the bird.)
Another good buy is a Herbert Miner Pro Grade neck for about 25 bucks which will have a range of sizes most down to 18, but Whiting saddles might be easier to work with (more flexible thinner stems) and easier to find.
Since you’re just starting out, I think you’ll find that black is kind of a limiting color for most dries besides ants and a few caddis. You might want to start out with a grizzly, brown or medium dun (medium gray) instead.
Any of these colors would work with ants, and will likely be more useful for a lot of the other patterns you’ll be tying down the road. And since ants have short legs, I’d tie them with a smaller feather than the hook size, using a 14 feather on a 12 hook.
For wet fly hackle, you’ll want to use softer, webbier and less expensive stuff as other folks have pointed out. Woolly Buggers (with a marabou tail) typically run larger than Woolly Worms and might be a better pattern to start with. They are also very effective. A Bugger pack would be good for them (about 13 bucks), or you could get a pack of black strung saddle hackle for about 3-5 bucks for either woolly buggers or woolly worms.
Again, actually being able to pick stuff up in a fly shop and having someone work with you to select stuff out is a great advantage, especially with natural materials like fur and feathers because of all the confusing choices as well as the wide natural variation between individual critters in terms of size range, number of twisted stems, color etc.
Hope this helps.