What’s steemit?

I just heard about steemit being a great platform to write and get paid. Last night i just wrote something that was on my mind and i got few upvotes. I felt great about it.
But there are few questions in my mind which i would like to ask this community.
What’s steemit basically?
How could i benefit from steemit in a great way?
My writing skills are not professional so shall i be writing anything on my mind?
Can i copy paste any material which i find on steemit?
How can I possibly get more followers?

I love writing about religion, so can is it appropriate to write about religion here?
Thankyou everyone. I hope I’ll be a better part to this community.