I can't use track matte

In any lesson, I can see that when I click on the Track Matte tab, there are 4 options: Alpha Inverted Matte, Luma Matte, Alpha Matte, Luma Inverted Matte.  When I open this tab, I only have the option to select the layers I've already created, and I can't find an explanation of how to toggle this. (I'm using the latest version of After Effects) I just can't continue my studies because of this little problem(