Desperate need of help

Ok guys. I am an utter, utter beginner at this and i NEED to get this done for a project. I am using C++ with the VST SDK 2.4 to create a basic synthesizer with a filter of some kind (low pass, 3 band, anything). I understand all the DSP things because of my background but i just cannot understand how to link a filter in with my output from my audio. If someone could PLEASE help me immediately it would be INFINITELY appreciated.

here are some links to dsp filters. My main output is out1 and out2.

http://musicdsp.org/archive.php?classid=3#32

thankyou so much whoever kindly dedicates some of their time to this