Start with an introduction, here you should tell your reader your standpoint and then the rest of the essay is used to show why your standpoint may be correct or incorrect. For example 'Do all Christians agree on the creation story in Genesis?' from everything you have learnt you may believe that yes, all Christians do agree, this should be what you say in your introduction. Then your main body of the essay you may choose to structure it as a 'for' point followed by an 'against' point until you think you haven written all the points you know. Finally, your conclusion shouldn't include anything that you haven't already said in the main part of the essay. The conclusion should bring together all of the points you have made and whether you have decided this shows your stance in the introduction was correct or incorrect.