What's the difference between a relationship with God and a religion?

I was told that only christians will go to heaven. I was told that God isn't in the midst of confusion. I was also told that Jesus of Naz practiced Judaism. So needless to say i'm confused and I'm sure that i'm not the only one just based off the previous things that i was told. I was told that God judges me off of my heart not my actions. So if i live "right" (based on the right that i know) i could go to heaven. But what if i don't subscribe to a religion but follow the practices of multiple doctrins to be the best me, would i not qualify to be heaven bound? He judges my heart not my actions. Let's clear up this confusion.