Apache is no working for me. It was because I had removed some files through the folders, and then I tried re-installing. I re-installed apache; however, it's still not working.

I tried: /etc/init.d/apache2 restart
Because it was not working and I got this following error in the terminal:

Syntax error on line 160 of /etc/apache2/apache2.conf:
Invalid command 'Order', perhaps misspelled or defined by a module not included in the server configuration
Action 'configtest' failed.
The Apache error log may have more information.
...fail!

Please help. thanks.

Either restore your /etc/apache2/apache2.conf from backup (if you didn't make any now you know why you should) or follow the clues. The error message tells you exactly where to look:
...twice:

I had not made a back up; however, what I did is that I copied the missing files from another one of my computers in which I have apache installed as well. I tried starting or restarting apache after pasting back the missing files, and now I am getting this error:

kidgrave-RS482-SB400 kidgrave # /etc/init.d/apache2 restart
bash: /etc/init.d/apache2: Permission denied
kidgrave-RS482-SB400 kidgrave # sudo /etc/init.d/apache2 restart
sudo: /etc/init.d/apache2: command not found
kidgrave-RS482-SB400 kidgrave # sudo /etc/init.d/apache2 stop
sudo: /etc/init.d/apache2: command not found