I don't know if I exaggerate with the lights...What recommendation could you give me?
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Just from looking at it quickly... the character is lit all around. You are in (as i may assume) a dark tunnel of sorts. So there is no all around lighting.. correct? So how is that the back of your character so lit up? Don't be afraid to use shadows. Shadows make the world seem more realistic.
You should consider your scene. Where will you have light sources? Does the tunnel have some sort of lighting the path? If so.. where and what are those lights going be and look like.. Then apply them and see the result. You can experiment with different lighting sources, but don't have an all around lighting. Even when you go outside in daytime, an object will have some shadows..
Visualise your scene first and the outcome you want to put out... Consider looking at photos on google before making up your mind