Question: How can I export a specific page in Wordpress?

I want to use a page from one wordpress instance in another wordpress instance, both having same theme.

How can I do this?

Answer: 
Similar to *Ali Raza*'s answer, if you don't want to create an author to export just one page you can

* modify the publish date of the page to a date before the creation of the installation
* and while exporting select that date and export
* then change the date back

`(would've commented but not enough rep)`
There are many ways to do this. 

1. Download wp-coder plugin
2. Go to page which you wanna clone
3. Inspect Element and copy all html code and paste it in notepad. Also copy all code from style.css and paste it in notepad.
4. Now navigate to wp coder and copy paste html css where you wanna make same page

Note: install wp-coder where you wanna add same page