yukino hatake

how to see CM or M value in 2.8

Hey guys . after the second class i decided i wanted to try to model my own house. i did watched the house tutorial here but i dont know where i can find the lenght info in 2.8.
i would like to make the rooms somehow believable (not 100% since i am not an architect but i want to get close to realistic style .)
i hope someone can help me with this :)