Each page needs to have only one H1 tag. If you are using WordPress then by default the title of a page is wrapped into H1 tags.You can either choose to have the same <title> and <h1> tag or provide an alternative title for the heading.
As far as the other headings are concerned (h2, h3), the things you need to have in mind are the following:
*Avoid using a single word for a heading but make your headings interesting and useful for users that like to skim read an article.
*Use headings hierarchically i.e. the first heading tag is the <h1> and then the <h2> and then <h3>, <h4> etc.
* The subheadings are a great place to use related keywords in your content.