Words contain the voice and purpose of the story.
Pencils contain the action and direction of the story.
Inks contain the style and tone of the story.
Colors contain the mood and emotion of the story.
Or I could be completely making that up. It feels like an oversimplification because it is, but it's for learning, and in learning there must be simplicity above all else.
How do I choose a color scheme?
Easy. I ask myself, how do I feel? Or how do I want others to feel from my the image?
I decide on an approach to harmonizing color. Any Google search can show you how to use different patterns on the color wheel to discover natural harmonies. Otherwise without your wheel and your rules, you're just swimming in your own ideas of favorite colors and imagined colors.
Coloring is a real labor of love and is underappreciated. It's an entire art form apart from drawing. It's why abstract art or impressionism was even a thing. Color is kind of a big thing. And it's not easy. It takes a lot of practice and messy mixing to learn how to harmonize a color scheme.
Color is a messy workshop. It's not a drafting thing, which is really technical and tiring. Color is the work of a mad scientist. Check out Color: A Workshop Approach
It will take you through a variety of experiments with analog color projects that are easy enough to find the source material for each project. You can probably take a digital approach to it pretty easily, although I am in the camp of most traditionalists and that is to do it in the real world first. You'll be much more fantastic in the future and ahead of the game if you start analog and then jump into the digital (or start both analog and digital at the same time if you can keep it up).
Tints are the lightened versions of your colors (adding white or a version of white) and tones are darkened versions of your colors (adding black or a version of black). You'll see the tints and tones of my chosen color scheme below.
Color is erratically organized by nature. Go look and see! Spring is the perfect time to check it all out. I listened to this while I came up with my current color palette. Enjoy.