Color Guide Questions

I do not have much of a color theory background and am trying to use the Color Guide to select colors. When choosing a Harmony rule, maybe the Complementary color rule:

1. Can you select more than one base color?

2. Does it matter how saturated/bright a selected base color is? Are any orange, blue, yellow, purple, red, green that is chosen as a base color technically a complementary color regardless of its saturation or lightness value?

Thanks.