Fallout 4. Got a used copy of it but its why I spent 300 for a Xbox One

I like the Armored Cores series, wish they did more with it. I also like legends of dragoon.

This is probably a stupid question but I'm currently at level 52 and I'm surprised cause I thought there was a level 50 cap. So I was just wondering if anyone knows the cap, and would like to know at what level are you at.

Sorry I've been under a rock somewhere so what is the extended cut DLC?