How to teach a new dungeon master?
My friend is DMing his first session and decided to make an entirely homebrew cyberpunk themed session.
I was the one who introduced him to dnd and have DM'd a few games myself. I originally told him to do a pre-made module, but when he said he didn't want to, I approved and have been trying to assist him. It has been a few days since he started prepping, and he has made several additions and alterations to the game. For example, he wants to give players the option to dodge bullets or just tank the hits. So, every attack will be a contested roll rather than having an ac to make dex characters stronger. That is what he claims. (He mainly plays high dex rogues and assassins and isn't happy that his ac is only 15 at level 5. "He also isn't wearing armor.) I have also tried to encourage other ttrpg systems other than dnd such as Cyberpunk Red and Carbon 2185, but he doesn't want to. I want him to have a good time dming but am worried it will cause problems later on for both him and the players. What should I do?