I started out back with stick and tissue free flight, control line, then built and flew two channel gliders. Kind of self taught - I had a friend who flew better and talked me through some things and trimmed my glider initially. Then I thought I'd go to a powered R/C model. Built a Sig Kadet and strapped a .25 engine on her (the minimum recommended). Either because the instructions said, or from free-flight "experience" I hand launched her to check the trim. Mistake #1. After that minor rebuild I tried to fly her. Hardly moved in the grass. Hand launch under power. Mistake #2. After that major rebuild I tried several more attempts and did succeed in getting some air under her. Then a sharp turn turned into a knife edge landing. Sold the pieces.

20 years later I had a friend who bought a used R/C trainer from his brother-in-law suggest we join a club that offered instructions and instructors and learn together after I said I'd like to try again. Much better idea.

Sure you can teach yourself. But your chances are much better with help.

And there are a lot of surprises in the real world that simulators don't teach. Gusts, disorientation, thermals and footers (the bottom drops out), sun in your eyes, loose connector, wheel falls off, wasp up your pantleg, etc.. Some things can only be learned through educating and conditioning your muscles. Thumbs and brain. Beginners tend to overcorrect and overreact. You eventually fly ahead of your models, instead of reacting with and to them.