shopify website

Hi
I was wondering if you can help me add something to my Shopify .
I want to change the shipping confirmation email that my customers get .u use a fulfillment center for shipping.and when they ship something the customers automatically get an email confirmation with tracking number as a Link ?
I Will like to add a link before the tracking number so it conduct the customers to a different tracking website I can explain in more detail if this something you can do best.