Need help getting my mod started Thread

I'm honestly not sure where i should look for advice but this seems as good a place as any.

I'm currently in the planning phase of a mod for Master of Orion 2: Battle at Antares and before I get into the development bit, what do i need to get started and farther? Do i need to learn a language or is it as simple as editing text and picture files like a site said it was?

Firstly, I don't know that game so I cannot give you any specific directions.
I can say you this however.
How hard the creation of a mod is and which skills you must have, solely depends on what you're planning to do.

My first steps in the world of modding were modifications of the configuration files in GTA games. Stuff like making your car three times as fast and fifty times as heavy.
Later I modified the map files and scripted my own gamemodes for San Andreas Multiplayer.
Then I started messing with CSS and learned the basics of level design on a learning by doing basis.
And now I'm here. Started my first serious project some time ago and, again, keep learning new stuff (mainly Blender).

The point of this post is not to tell you my life-story (at least not the only one ), but to let you know that modding is no different from game development.
It's a very broad term. There are subforums for different areas here for a reason.

What do you need to know?
We cannot tell. What do you want to do?