How to get static page displayed in the

I am trying to configure sharepoint-like theme, how do it get my content shown on the content block on the same page, as of now the page is getting opened on a new window.

Where do I put the details of the my url to ensure that menu clicks displays the new page in content block of the theme.
I have this problem with all the themes, I know I am missing some configuration or key while passing the url.
Kindly let me know or point me to a page which gives me this input.

Thanks in adavance.