Colours are divided into three types

Primary colours

Neutral colours

Secondary colours

Primary colours are:

Red

Blue

Yellow

Neutral colours are:

Black and white

The secondary colours are the colours that result from mixing primary or neutral colours.

Now you have to learn this it is very important:

Yellow + blue = green

Yellow+ red=orange

Blue +red=purple

Yellow +blue +red=brown

You can learn it better if you apply it yourself and discover yourself.