How I can memorize scales and chord progression for guitar?

I've been playing guitar for almost 12 years and I know that some of the basics and how music theory works, but I always find myself playing the same notes only know because I know that sound well together. Now I am overwhelmed trying to find a way to memorize what notes you can and can not play, while in certain keys and scales. Is there anything or anyone out there help me step by step so you can reach a level where I can say, "let's play in E" and then know what notes to hit and what not? HELP! lol

PRACTICE! I had the same problem and practiced a lot. also try to get a guitar teacher

Guitar Lesson – Nashville Numbers (Chord Progression Theory)