The wording of your post isn't completely clear. The second sentence sounds like you want to use your broadband to provide an internet connection to your phone, but the last sentence sounds like you want to use the phone's internet on your desktop.
A computer using the phone's internet connection is called "tethering" or "USB tethering". Many phones support that out of the box - I'm not familiar with your model, and if you bought it through a network they often remove the facility from the software.
The phone using the computer's internet connection is called "reverse tethering". This is less common, and I don't think any phone supports it out of the box. There are ways, such as described
here, but most of them require rooting the phone first and may also require support for tethering as well, so do your reading and make sure you understand the requirements before trying anything. But if it is that you want, searching for the term "reverse tethering" will give you the information on how to do it.
(The more common way of sharing a desktop internet connection is wirelessly, but I assume you knew that and have reasons for wanting to use a cable).
