Fly fishing reels are normally operated by stripping line off the reel and wrapping it around the fingers with one hand, while casting the rod with the other hand.
You normally hold the fly rod in your dominant hand and manipulate the line with the other close to the reel, pulling line out in small increments as the energy in the line, generated from backward and forward motions, increases.
Fly fishing is very rewarding but takes considerable practice.
You'll find lots of information on how to cast, select a rod, select the appropriate line on the Take Me Fishing website.