The chances are, if you’re asking yourself this specific question, you’re probably feeling some sort of draw towards paganism. Don’t be alarmed: this is quite common. Ask any passing pagan how they came to be pagan and I’ll bet you carrots to cubits that they will reply with some variant on, “I just realised it’s what I’ve always been.”
The best answer I can give you to this question is simply that You Will Know When The Time Comes, Grasshopper. (Actually, I’m not sure Master Po ever actually said that to Caine, but it sounded like the sort of thing he might’ve said.)
It’s a little misleading to think of paganism as something you have to ‘join’. But then, it’d be a little misleading to think of any overall religious philosophy in that way. You don’t have to ‘join’ Christianity, for example: you either believe in the basic tenets of Christianity or you don’t. If you find yourself drawn to that path, then you might, it’s true, undergo an initiation ritual. If you’re a Roman Catholic, you would probably have been baptised with holy water on the forehead as a child, but would need to be ‘confirmed’ into the Church when you’re old enough to make the commitment for yourself. In other traditions, such as the Pentecostal and Baptist churches, baptism involves full immersion in water as your adult commitment. But being a Christian doesn’t strictly require any of these things: all it needs is a belief that Christ died on the cross to redeem your sins.
So it is with paganism, in many respects. You can join a Wiccan coven and undergo training and eventual initiation. You can join a Druid order or ‘grove’ and be initiated into their tradition. Such a requirement might be part of a given pagan path or school, but to be pagan is something more felt than decided upon. It’s something you are, and there’s even been debate in modern times as to whether one can be pagan and still follow a monotheistic path such as Christianity or Judaism. Some insist aye, some give this one a hearty and resounding nay.
But, to give you a short answer: a website can’t tell you if you are or aren’t. You’ll just know.