The classic essay structure looks like this:
You can vary it, of course, but this is the format I learned in High School and it's served me well all my life.
You usually want at least 5 paragraphs. The intro introduces the topic, discusses it generally, but narrows down to the specific claim you're trying to argue in the last sentence. (From general to specific.)
Then you write 3 paragraphs, each with a different fact which supports your claim.
Then your concluding paragraph summarizes your points, hooking them together to show how they support your claim. Then you briefly talk about the broader impacts of the claim. (From specific to general.)