Hey Jessie, welcome to the forum. What kind of fish will you be chasing? --- There's lots of smallmouth, largemouth, panfish and carp fishing you can do as well as trout fishing in the Blue, Broken Bow and Lower illinois.
If you're going to fish for trout, you might want to check in a local fly shop like Three Rivers Fly Shop Three Rivers Fly Shop - Broken Bow, OK
in Broken Bow OK. They can help with some good suggestions based on recent conditions ( water levels, temperature, and recent hatches) and can also give you some pointers on techniques, rigging and where to go.
You can also pick up some basic stuff like a couple black and olive weighted woolly buggers size 8, some nymphs (pheasant tail and 18, gold ribbed hare's ear) and some dry flies (Parachute Adams or Parachute Blue Wing Olives 16 and 18, Elk Hair Caddis 16, Griffith's Gnat 18) and some pink and apricot colored egg patterns. These are go to patterns for trout pretty much anywhere and would be a good choice as you start to stock up a fly box.
Since you're new to fly fishing, you might want to see if there's a fly fishing group near you. Groups like Trout Unlimited (TU) and clubs affiliated with the Federation of Fly Fishers (FFF) have informative meetings, casting clinics, tying classes and group trips to local waters-- and it's a good way to meet some new fishing buddies. You'll learn a ton and get a lot of help getting started. TU has a few chapters in OK and so does the Federation of Fly Fishers with 3 affiliated clubs in Tulsa, Tahlequah (NE OK) and Bartlesville (Greene County)
You can do searches for contact info here:
for FFF affiliated clubs: Locate a Club
and for TU: Council/Chapter Contacts | Trout Unlimited - Conserving coldwater fisheries
Hopefully some folks from Oklahoma will jump in here with more suggestions, but feel free to ask questions as they come up for you-- folks here are pretty friendly so just make yourself at home.