Hi Daniil,
Welcome to our community! 
Is your material white? If so, that’s the default colour. In Rick’s case, it is white, too, but the lighting in his scene was not generated. That’s why it looks so dark.
Please go to Window > Rendering > Lighting Settings. At the bottom of the Inspector, click on “Generate Lighting”. You could also try to disable “auto-generate lighting”.
Did this help?
See also:
- Forum User Guides : How to mark a topic as solved