i am using a fingerprint scanner using the printer port for my 4th year project i have to access windows apis how do i go about that

You have two options to getting this to work... the first option which probably is the most robust is to develop a driver which attaches the device to your system like a regular scanner, or find a driver that already does this and learn how to interact with the TWAIN scanning interface in Windows.

Other option is to learn how to get direct access (or access to the memory) which controls your printer port and send and receive data with the device at a raw level, and write this support directly into y our application.

http://msdn.microsoft.com and http://www.microsoft.com are the best resources for both of these options. Oh, and you will probably be able to pull up info from http://www.google.ca