How do I use an open face spinner reel to fish for trout on a river in Missouri, can i fly fish with this reel?

Try spinners or spons OR if you have live worms or minnows use a splitshot and a hook, cast upstream and reel in slowly as you bounce the bottom. You can also bottom bounce yarn flies (easy to tie) or real roe sacs. Bottom bouncing is deadly for rainbows and brookies. Not good if there's lots of snags. Keep your line tight while river fishing so you can get a hookset.