If you want to train your fingers to operate individually, just do a simple pattern like this:
e----------------------
b----------------------
g----------------------------etc
D---------------------5-6-7-8--------------------------
A------------5-6-7-8----------------------------
E---5-6-7-8-------------------------------------
keep your hand in one position, one finger per note. Play it all the way through, up and down a couple times to warm up, then start playing only the notes your 1st and 3rd finger are over (with only those two fingers), then your second and fourth, then your first and second, your third and fourth, your second and third, your first and fourth. Then play the E string with your first and third, the A string with your second and fourth, and alternate between them for the remaining strings. Keep mixing up what you're doing in a similar way, spending about the same amount of time on each finger. Do this for about fifteen minutes or so at it when you first pick up your guitar to warm up and slowly your fretting will improve.