About linux : How-to-Fix-Could-not-get-lock-varlibdpkglock-Error-on-Ubuntu

I have recently started learning linux commands and got this error while installing any application on Ubuntu.How to resolve this?

How did you try to install app?
Did you use apt?

If so, maybe some other apt process is running in the background or you have opened Synaptic package manager.

Run sudo killall apt apt-get and please try again

if another package is in progress for installation/removal then in that case you are going to install/remove second one package you will face Unable to acquire the dpkg frontend lock error