Installing a package manually using apt-get

I'm trying to install a deb package offline using apt-get command. From what I understand, I can download a package manually from the internet. Put it in the local repository folder (which is usually /var/cache/apt/archives). Then update the repository using apt-get update. And finally apt-get install myPackage I tried these steps, but I keep getting the error Unable to locate package uex_15.1.0.8_amd64. What am I missing? or should I use apt-offline? If so, how? BTW, the package uex_15.1.0.8_amd64 is the package to install UltraEdit.