Can't change the screenshot directory because "com.apple.screencapture: command not found" I used to be able to change the screenshot directory by just changing the location and typing in the specifics to the terminal but now I am getting this code and I have no idea what to do.

I went through everything a month ago to manually erase everything because my Mac was running slow. I think I might have accidentally deleted something I needed. What should I do? My desktop is getting extremely cluttered. I am using a MacBook Pro with macOS Sierra.

MacBook-Pro:~ ChristianJ$ 
MacBook-Pro:~ ChristianJ$ com.apple.screencapture location /Users/mac/Documents/Zoology/edited\ screen\ shots
-bash: com.apple.screencapture: command not found
MacBook-Pro:~ ChristianJ$
The error message is telling you that the shell (bash) is expecting the first expression on the command line to be a program, script, or shell built-in. com.apple.screencapture is none of those.

The command you are missing is defaults, with a sub-command of write, like so:

defaults write com.apple.screencapture location /Users/mac/Documents/Zoology/edited\ screen\ shots