How can I fill an area with light green concrete in MCPE?

I want to try something in mcpe (Minecraft pocket edition) and for that I have to fill a large area with light green concrete but I don't know how to do it with a command

You choose 2 positions from where to where the green tone should go. Then you remember the coordinates of the two positions and write / fill x1 y1 z1 x2 y2 z2 green_terracotta

or whatever block it should be

If green_terracotta does not work in the PE version, look for the BlockID for this block from the Internet