I've been give a task to write a short C/C++ program to
extract files from a .deb file on windows platform
I know there are tools like 7zip that do it but I need
to code it).
Could someone please give me a push in the right direction
(too much rust and too little experience :$.)

In wikipedia (http://en.wikipedia.org/wiki/Deb_%28file_format%29)
I can see the following:
a deb file is implemented as an ar archive.
Canonical contents of this archive are three files:

* debian-binary: deb format version number.
This is "2.0" for current versions of Debian.
* control.tar.gz: all package meta-information.
* data.tar or data.tar.gz or data.tar.bz2 or
data.tar.lzma or data.tar.xz: the actual installable files.

The debian-binary file must be the first entry in the archive,
otherwise it will not be recognized as a Debian package.

This page has what you need to know about ar archives:

Start by extracting the three files from the .deb.
Then you can proceed with the important part, i.e. extracting the desired file(s) from the data archive.