child’s template differ from parent’s?

Hi-all, I am new at this and this question strikes me as fairly basic but I feel like I am banging my head against a wall.
I am trying to use wordpress to design a simple site with 6 different pages. I want the headers and the footers and the sidebars and all that jazz to be the same but the main contents to vary in design (a blog, an album, a simple text field…) Is there a way to change the code for the main body of child pages to differ from the parent and siblings?
So far I have gotten around the problem by creating each page as a parent but duplicating changes 6 times is making me crazy.

Experienced wordpress users Please Help Me!
https://www.ridetheycried.com/about