the outsiders

I couldn't relate to the book so the only thing I had to ask is a few questions. Why is soda giving ponyboy advice about darry and how not to mess with him? Then why was jhonny protecting pony boy and why did he choose to save him?  I got kind of confused because first they talk about  their own gang then switch to the other gang the socs that's the rally big thing on my mind about this book.