Learning the fundamentals first (such as networking) is a good way forward. You will propably need to learn many other subjects along the way, such as how system services are handled, permissions in linux, linux system administration in general and so on.
If you just want the fundamentals of networking, these resources are pretty good:
Feel free posting to this community with questions or try finding someone who can be your ballplank. Getting started can be very challenging before you’ve grasped the basics.