How Do You Recall That Note B and E Have No Natural Sharp Key?
Practise all the scales along the length of one string just like a piano player would along the keyboard.
Notes A and G on a guitar jump every two frets except E and B.
To remember that notes E and B are different try and recall the Elephant-Bee this should jog your memory not to go up or down two frets when you go from an E or a B but one step only.
So now you should play and practise a C major scale (i.e. notes A B C D E F G (with no flats or sharps)) remember that there are two frets between each of these notes except E and B where there is only one.