Read about fishing, duh. The internet is full of stuff. Buy a book or two. That is what I did years ago when I wanted to become a better fisherman. It helped, but I still was never great. You can learn about the importance of things like time of year, temperature, location, structure, bait, rigs, etc. Some books will even give you locations (I bought a book at Walmart two decades ago, and it actually gave quite a few decent fishing locations in my area. Someone mentioned local fishing forums. Those also have useful info. I have met people out fishing who taught me stuff and even invited me to fish in boats and better locations, etc. I would tend to be more careful nowadays, though. Mot of all, keep fishing. Experience is a great teacher, after you have the fundamentals down, anyway.