Here are some links as an overview:
Here's where you should start if you're brand new:
Now you can see what's next:
Take it case by case:
Solving an issue number or developing a feature when working with somebody
else's repo (PR) may differ from just working on your stuff dictates which is
appropriate.
There's a reference link below; investigate cases requiring edits in the config. This could be a local change for the repository or global settings. Look into how the ssh credentials work.
Check out the resource on the wiki here.