Of course, the great bulk of the important action of the Civil War was undertaken by white males. However, African Americans and women did play some part in the war. The parts played differed to some degree in the North and the South.
On both sides, women’s direct participation in the war was generally not in combat. Instead, women served in supporting roles. Women served as nurses, for example. Some of them worked as cooks for the soldiers or worked doing their laundry. In other words, they served as support to the soldiers. The other major role played by a number of women was spying. Some women acted as spies, in part because they were less likely to be suspected by men.
African Americans played a much more direct role in the North than in the South. Very few African Americans were allowed to fight for the South since the South did not trust them. Slave labor was, however, used to do many things like the digging of trenches or the loading and unloading of war supplies. In the North, African Americans were not initially allowed to fight. However, as the war went on, the Union did start to accept African American soldiers.
Thus, African American men played a more direct role than white women did, but both types of people did participate in the war to some degree.