Difference between fore and hind milk?

I’m new to breast feeding. I have been exclusively pumping due to baby also being fed formula. But we are working on getting him to breast feed. My question is this:

When I pump, I pump for about 10 minutes and by then I’m not getting much of anything else out. Even with massaging and warm rag. I usually get 2oz, but most I’ve gotten was 3oz combined. I’ve heard of fore and hind milk but I don’t know the difference. I’m not sure if I should keep trying to pump and see what comes out? My boobs sometimes still feel full after pumping even tho nothing else comes out.

Here’s a milk of stored milk for reference I guess.