i just got photoshop. i do not understand how people get pictures onto their sig area. i know how to open new file and make it sig size. but cant put a picture in it. everyone keep saying put the render in but i do not know what that means

render is the cut out of ur focal (usually). ctrl/cmd + a, then switch back to the sig sized document, and ctrl/cmd + v.

also, since you know NOTHING about photoshop... start reading a lot of tutorials... google stuff on bing for the basics about photoshop

It's a simple drag and drop process.
just open the image you want to place in the sig and drag it over to that canvas