How to link from a ‘page’

Hello – I have a site and there are pages at the top that link to the various page info. But what I want to do is to link to and external (non-wordpress) directory within my site.
Is this possible and what code to I need in the page to execute this? In addition to wanting to link to the external directory I want it to open a new page can I just add target=_blank to whatever code I need to execute?

I have EXC-php as a plug in if this is required.

Thanks so much