New to Keto

Hi everyone I have a question. What happens if you go over your fat intake but can’t get in the amount of protein? Just starting confused and worried if I’m doing it right. I’m a lap band failure I just got great a throwing up. I had all my fluid withdrawn from my band and gained everything back. I feel better then throwing up even in my sleep but I want to be strong. I workout at a the gym every morning with a great group of people, but realized at 52 I don’t know how to eat correctly. Life is too great to be weak and tired all the time. Day 2 of Keto and down 2 pounds already🙌🏻