Dutch Baughman, a fly fisher from Texas, has this excellent website with PowerPoint presentations free to download.  The website is intended as a personal resource to explore your fly fishing journey. Each Fly Fishing Topic includes a slide presentation or document you can download to your computer free of charge. This is intended to help the individual fly fisher as well as Fly Fishing Clubs.

If you are interested in fly fishing and fly tying this is a must. I recommend checking out the one on wading safety.

https://www.flyfishingskills.com/