Click the Fill box in the Control palette. (The Control palette is at the top of the work area, just beneath the menu bar. If you don’t see it, choose Window > Control Palette.) This tells Illustrator that you want to apply color inside the shape rather than to its stroke (or outline). Then click any swatch to fill the shape with color.
If you don’t like any of the default swatches, there are several other ways to select a color. Double-click the Fill box in the toolbox to select a color using the Color Picker, or choose Window > Color to select a color using the Color palette. Or choose Window > Swatch Libraries, and choose a swatch library from the submenu.
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