The first thing you need to understand about a template is the difference between an image and a graphic. An image is what your visitors see on the front of the card. With a template, though, you don't need an image.
In order to be able to get a free template, simply go to an internet site that offers a template for Indesign Business Card Size. Simply browse through the various templates and choose the one that you like. If you're looking for a particular layout or design, you should be able to find something available online.