Aphelios isn't complex at all and Infernium R needs to be gutted and reworked.

Aphelios AKA ranged RNG Udyr on steroids, is actually a really easy to champ to play and master.

Aphelios from his primer may seem complex, but the truth is he is really very basic. He only has 3 buttons 2 of which you rarely press so mechanically he is probably the easiest champ in the game. His weapon system also may seem complex but if you follow some basic principles you'll start to understand it's not really that complex and mostly about RNG. While laning you always want Crescendum, the Chakram or Severum, the Scythe Pistol in your off-hand the second being the better of the 2. These weapons are massively OP in 2 v 2s and ganks and you want put them in your offhand any time you get them, then swap to them in all in and ganks. The second thing of note about the weapon system is Infernum, the Flamethrower+R combination is the single most busted damage ability to even grace and MOBA. If you land this incredible easy to hit, hard to see, long ranged attack massive AoE on 3+members any non-tank will instantly die. What this amounts to is before teamfights you wanna get Infernum in your offhand and simply swap to Infernum and press R to win fights. On top of that since his R is so OP and crits you wanna build full crit every game.

Other then that simply use whatever weapon the game gives you and so long as you read what they do and play based off which one you have you'll be fine.