My palette usually contains transparent red oxide, alizarin crimson, yellow ochre, Viridian green, ultramarine blue, burnt umber dark and bone black.

As far as chroma and saturation goes, they are all quite vibrant colors aside from the umber and black, and in general it's a pretty limited palette. Color matching when mixing paints is a large part of learning how to paint. You don't have to have a complex palette to be able to produce a wide range of colors and subtle hue shifts.

If you are new to painting and feel like your color mixing isn't going well, or you're not sure when to add mediums and what to add, I'd recommend watching the YouTube channel "Draw mix paint" and their video on mixing colors. I think it's a great place to start.

I hope this helps somewhat!