If you're using very bright colors such as the cadmium ones you might stick to the printing spectrum ( bright cyan, lemon yellow, magenta ).
In fact these are the correct substractive primaries (cyan, yellow, magenta) but because paint pigments are not chemically pure they don't mix this well in practice. That's what most art teachers will tell you. In reality tough, these days the amount of pigments is so wide that you can do it the physically correct way. Nevertheless, blue, yellow and red still work fine. Just saying that most color theory around is based on faulty dogma. That doesn't make it less valid, just dogmatic.
Note tough that you'll need to do a lot of mixing to tone them down enough. Should be good practice tough.
In reality there's a lot more to pigments tough, and painters tend to use a wide variety of them depending on the mood they're going for as well as their personal preferences. Some pigments are more opaque and others tend to be very agressive (vermillion, black, cerulean blue, etc).
Also get ivory black and titanium white. And perhaps if you want a warmer white.
You can mix a good gray with them you can use to tone down the chroma of your colors.
In the end tough, you can make almost any color combo work if you know how to use it.
So just have fun with it, don't focus on learning academics too much at this stage. Just get used to the materials.
If you want to learn more about color theory, check this link:
http://www.huevaluechroma.com/You WILL be confused by it tough! Needs some time to sink in

A generalized overview of the color spectrum:
Additive Primaries - Light: Red, Green, Blue
Substractive Primaries - Surfaces: Cyan, Yellow, Magenta
Warm hues: Red, Orange, Yellow (1)
Cold hues: Cyan, Blue, Violet (1)
Neutral hues: Green, Magenta (2)
On the warm hues gray will look cold.
On the cold hues gray will look warm.
On the neutral hues gray will look neutral - this is purely theoritic.
( CIELab color system: 1: 'Temperature', 2: 'Tint' )
Color values:
Dark to light to dark:
Violet (darkest), Blue, Cyan, Green, Yellow (lightest), Orange, Red, Magenta, Violet (darkest)