To find cells filled with a particular color in Excel, you can use the Find and Select feature.
First, select the cells that you want to search. Then, on the Home tab, in the Editing group, click Find & Select (or press Ctrl+F).
In the Find and Select dialog box, click Format. In the Find what box, click the Format button (or press Ctrl+1), and then click the Font tab.
Click the drop-down arrow next to Color, and then click the color that you want to find. To specify additional search criteria, such as font style or size, click More.
When you have finished specifying your search criteria, click Find All (or press Enter).
Excel displays all of the cells that contain the specified color. To quickly select all of these cells, click one of them, and then press Ctrl+A.