Designing Header (add picture) in WP with Genesis/Prose Theme

Hi–
I am totally new, and know nothing about coding/programming. I am waiting for a book to come in the mail…. 🙁

I am trying to set my preferences/designs for my theme (child theme, I think is what it is called). I have text in the header, with a tagline, but every time I try to put a photo in the header, it gives me a tiny little moveable box with which I am supposed to crop my photo–the handles don’t expand, and it ends up copying about 1/5 of my photo over, and I have to keep deleting it. Maybe it is adding it as a background??–but I already have a background chosen….

Maybe I need like a “text box” like I used to use in Publisher–know what I mean? The photo is to be used in its entirety, as a logo. I will want to put it on every page. Also, I would like there to be some differentiation between my header space and the rest of the page. Right now, the background is all the same color, and it looks like one big page. I need some kind of border line or frame around the header area (I also thought I chose a different color for that area, but it is not showing up). Any help is greatly appreciated!
doglegbipolarjourney.com

Paula