This is all poetic language, really.
"Well you done done me and you bet I felt it
I tried to be chill but you're so hot that I melted
I fell right through the cracks
And now I'm trying to get back"
This implies he and the girl ( I imagine) had a brief close relationship "you done done me" - US informal, slang.
He tried to act cool about it, but she was so "hot" - attractive, physically attractive that he lost his ability to act cool.
"I fell right through the cracks" - symbolically, he was so busy trying to act cool he let her get away from him, let the relationship falter. Now he wants to restart it - "I'm trying to get back."
"Divine intervention" - as Theo said, "divine" means "by God" in this use. So only God will be able to stop him getting back close to her, since he is so determined.
"God-forsaken", used literally, means small, mean, of no value, wothless, miserable - abandoned by God. Here, I think he uses it in contrast to a typical "God-given right" - something that we are entitled to by being human, just for the sound of it. It makes no sense, interpreted literally! I hope this helps ;)
As an example of how people see very different meanings in songs, you might like to look at
https://www.songmeaningsandfacts.com/im-yours-by-jason-mraz/