What's the difference between "at the door" and " in the doorway"?

"At the door" and " in the doorway" both are having the similar meaning, but their difference is
"At the door": you will see an object or a person after you open the door
" In the doorway": you will see an object or a person in a door that usually open

at the doorway是在那個"地點"的地方.而in the doorway意思就是他已經在裡面了.

doorway 是出路，有門或冇門