如何在內部硬碟建立Volume?

請問如何在這個終端機指驟輸入指令

並在內部硬碟建立Volume?

Launch Terminal and execute the following command:
tmutil deletelocalsnapshots /

# Do this for all other internal volumes as well
tmutil deletelocalsnapshots /Volumes/your volume

這是我哪邊的volume?