Welcome to our little corner of the world of SBC’s [Single Board Computers]
To get started I would suggest the following:
Perhaps start with the videos section.
I’m not trying to fob you off here… it’s just that the Raspberry Pi group has put a massive effort into their information and it is getting pretty good now. There are several club members who have done a lot of this stuff and are happy to assist.
For some inspiration have a look at these Youtube How To Build A Raspberry Pi Field Computer
Please note I am not actually recommending these particular projects, I just grabbed a couple of examples of enthusiastic amateurs getting their Pi’s doing things.