Hello Karthik
as beginner it sounds as thick as two short planks,but its very easy.there are two parameters that you have to remember.
Transmission and reflection parameters(transmission s12 ans s21) reflection(s22 and s11). s12 is the power that is transmitted with respect the total power,s11 power that is reflected to the total power. and same for port 2.
cut down the math first and look at it this way and then you will be able figure it out fairly easily.google up s-parameters there is a nice presentation from polar instruments check it out.
Regards
Rotmanlens.