Let's look how to catch fish in Minecraft. First, you need a fishing rod. You need three sticks and two pieces of string. Put them there in a fishing rod like arrangement, and then you need some water. Just right click to throw the line, oh that was perfect and I missed it. Right click to throw the line and when it drops down into the water, right click again, and you'll pull the fish out. So, there you go, the fish will fly out and you catch it, and then you need to cook it.
So, to cook it, put it in a press, put some kind of fuel there and that'll cook up your fish good. Then once it's cooked, you'll have a cooked fish to eat with, but that's not the only place that you can fish. You could also, you could also just fish in some water that you've dropped down. So, just make sure that the hook thing is still floating, as you can see it's bobbing up and down, as long as it doesn't get stuck to anything, you'll still be able to catch fish.
Anyway, so, our cooked fish is out, and then you can just eat it by right clicking.