[konroy]

currently there exists a light with 14/2 wire with the whites tied together and the black wires top and bottom of a single switch. what do i need to do to tie in the fan to make the switch turn on the fan and light with one switch at the same time?

 

[Piedmont]

From the fan, run the wires to the light and inside the lights box tie all the whites together with a properly sized wire nut, all the blacks together likewise, and all the greens/bare copper together.

This isn't something usually done at the switch unless the fan & light are currently on seperate switches already OR you want the ability to later put them on 2 seperate switches.