" get a multi package of threads with a variety of colors to cover all the options for different patterns or would it be best to buy individual spools..? Are there any preferred colors to get over others, same goes for hackle/feathers and other materials..?"
I would get individual spools of thread. I could be content with Danville's 6/0 waxed nylon in olive (it is a dark brownish olive). Black is good, too. Or, you could get a spool of white thread and a selection of colored permanent markers. If you get into spinning hair, you'll want heavier thread.
For materials, I like natural materials in their natural colors the best. A full hare's mask will let you create dubbing in a range of colors.
I agree with the advice above. Pick a pattern and get the materials for that pattern, then tie a couple of dozen. Repeat with a new pattern. You will build up a collection of materials and your tying skills at the same time.
It's a great hobby!