As a beginner, or for someone coming back to the sport after a long lay off, your fly fishing presentation concepts probably will center around the mechanics of casting. As in any sport/outdoor effort, the mechanics of the activity are important for success and safety.
However, I would encourage you to give equal or perhaps even greater emphasis to the food sources for fish and factor that into your presentation. The worth of a fly pattern is more important than dry, nymph, streamer tags. What do your targeted fish eat? How does that food source move in/on the water? Where are the food sources within the water column? How does that information factor into how you present the fly to the water?
This critical information in understanding the big picture, particularly if fishing blind (to the unseen fish, that might be holding nearby). How you present the fly will often be your assessment of what is emerging before you, or what your studies have shown to be likely present within the water.
Study the food sources. Study your mechanics of casting and how to cast. Study holding lies of fish (where they tend to rest and why they hold there…food/rest/safety). And, if you venture into fly tying (which I hope you do) then eventually learn what that fly is imitating (say, March Brown, Blue Winged Olive….) and then study the life cycle of those mayflies.
Fly tying is a very creative, innovative past time. Don’t let the artistic, creative, innovative side blur the underlying intent….to mimic a food source that incites the take. Learn the food sources, buy/tie patterns that match food sources, learn how to present that food source in the most probable holding lie and good luck. Later, you can tie experimental patterns that perhaps don’t match the real food sources but still attract the fish’ attention. All part of the fun!