What are the core beliefs of Presbyterianism? How does it differ and compare to other denominations of reformed Protestantism?

I have never thought of myself as being overtly religious ever in my life (in high school). I have never gone to church, but what I am now realizing is that I have been raised (more or less) as a Presbyterian. I come from a long line of Scottish heritage. All of my family has been religious and my great grandfather was a Pastor. Would it be stupid to say that I am a Presbyterian who has been raised away from the larger bodies of organized religion since Presbyterianism is mainly an organizational doctrine? I have recently met some (I believe) Reformed Baptists that call themselves Reformed Charismatic. They are very entranced with John Piper, who I have read is not reformed, so how does that work? I really want to use this as an opportunity to actually embrace religion. My understanding of Christianity is very barebones but I know more than the average person in our hyper-secular world today. What I need is a longer explanation so if you know anything that would help, please link it, but a reader's digest version is greatly appreciated. The main things I think I need to know are (1) what are the main beliefs of Presbyterianism, and what do I need to know to pass myself as one until I get further into it, (2) what is a good way to comprehend Biblical fundamentalism from a Presbyterian view, (3) what is the difference between other forms of Protestantism and Calvinism (especially the Reformed Charismatic denomination)?