Can I Edit the Source Code?

We are trying to have the Phone number of the customer show up when we open up and view the order they submit

Editing the source code isn't open to our customers. The closest you can get is by adding styles and javascriptscript to the few customizable areas, such as Header Content on the Theme settings page (instance.allmoxy.com/settings/general).

Without modifying the system, the quickest way to find a customer's (company) phone number (from the order form) would be to follow a link to an output page designed to show the customer's company phone numbers.