Keywords first and foremost should be located where they make sense. Don’t force them into a place just because you want that keyword.
With that said, Keywords should be in the page title, description, Img Alt tags, headers, and a few times in the content. Since each page needs to be unique I recommend focusing on a main keyword per page or post. That way you can focus on that keyword and all of the content on the page is relevant to the specific keyword.