Could not exec dpkg!

Firstly,i put the "dpkg" file manually to /user/bin/ directory and
then check the permissions by the command:
ls -la /usr/bin/dpkg
But it showed no dir or file named "dbkg"

Then i tried to change the permission as a sudo user but it did not
worked, so i entered in /usr/bin/ as a root user and change the
permissions of the dpkg package to the executable permission. This
trick works and then i run "apt-get install dpkg" and it showed an
error as:
E: Sub-process /usr/bin/dpkg returned an error code (1)

So, i run the following commands as a root user:
apt-get clean
apt-get autoremove       #it removes the uninstall cups package in hplib package
apt-get update
apt-get upgrade             #it takes 2 hours to upgrade the system

Then i exit from root user mode and run the following command as sudo user:
sudo apt-get -f install