RED , YELLOW & BLUE are group of 3 Primary Colors from which all other colours can be obtained by mixing.

@graphic_artist_sumedhajain

@artndesign_by_sumedha

A Secondary Color is a color made by mixing two primary colors of a given color model in even proportions.
Like -
BLUE + RED = VOILET
RED =YELLOW = ORANGE
YELLOW +BLUE = GREEN

@graphic_artist_sumedhajain

@artndesign_by_sumedha

Combining primary & secondary colors in the same manner produces a Tertiary Color.

BLUE+GREEN =BLUE GREEN
BLUE +VOILET =BLUE VOLIET
RED+VOILET = RED VOILET
RED+ORANGE = RED ORANGE
YELLOW+ORANGE = YELLOWORANGE
YELLOW+GREEN = YELLOW GREEN

@graphic_artist_sumedhajain

@artndesign_by_sumedha