But that's what's supposed to happen, the environment lighting is supposed to interact with the character -- this is the only way to create a mood / atmosphere. A dark scene with a green fill light and bright yellow rim light, for example, it will affect your palette but the player still has the dark and bright hints to…
Look into color theory and art fundamentals. These kinds of skills are essential for Art Directors and Concept leads. For example The Aesthetics of Game Art and Game Design, by Chris Solarski... https://www.gamasutra.com/view/feature/185676/the_aesthetics_of_game_art_and_.php More here…
This isn't an issue specific to games. Learn about the advantages of using a limited palette. A classic example is the Zorn palette of four colours. Buy some cheap paints and practice mixing them. In the distant past, games were limited by the hardware to use a limited number of colours for every game. This was a good…