The diamond elytras mod

Hello everybody,

Recently, I wanted to create a Diamond elytra mod: Just normal elytra but they can give armor like a diamond chest plate when you wear it.

I tried to make it in the armor case but I'm not very good at coding and I would like to make an event like when you wear the elytra and you fall from a high place you aren't gonna fall and die, you just gonna plane and not gonna receive damages when you'll fall

PS: I'm French so I'm not very good at English sorry

Thanks