@Tito Tim is right. but let me give you a bit more detail.
The reason for a "green" screen is because the specific color green is almost never used on sets or in the actor's clothes. But chrome or delta keying just focuses on a color. So while green is traditional, it isn't required. You can use any large fabric that is a solid color and doesn't math anything in your set or clothing.
That said, Tim makes a very important point Good lighting reduces the color range of the backdrop and makes it easier to key out. In a wire way, shadows and bright spots require you to key out a wider range of color and has a much higher chance of having something you don't mean to key out disappear