How and what should I use to makey own game I can own. Thanks
It you really want to start a fresh game, you'd need to learn how to code / program; for example in C#, java or python. That's for all the rules going on and displaying the graphics. That's the most important thing. Learn that on YouTube.
And then you also need to make the graphics and units, which can be quite fun. That can be done with blender, a free tool for making 2D/3D graphics. Learn it on YouTube
And at last you need a good concept for your game. What you want to do and what you don't want to do. Remember, almost everyone has ideas, but few make them happen.
Best of luck!