I am trying to download Adobe Flash, and these are the instructions I was given:
1. Click the "Download Now" button. A dialog box will appear asking you where to save the Installer.

2. Save the Installer to your desktop and wait for the file to download completely.

3. Unpackage the file. A directory called install_flash_player_7_linux will be created.

4. Navigate to this directory and from the command line type ./flashplayer-installer to run the installer (Note: this can only be run from the command line). The installer will instruct you to shut down your browser(s).

5. Once the installation is complete, the plug-in will be installed in your Mozilla browser. To verify, launch Mozilla and choose Help > About Plug-ins from the browser menu.

How do I unpackage?

What/Where is the command line? please help

Probably, if you right click on the icon of the downloaded file, one of the options will be, "Extract here."

Depending on your distro, you will probably find "Accessories" on the start menu, and one of the options there is "Terminal"

These questions are so rudimentery that it's difficult to generate the effort to answer them. I think you should spend a day or two studying Linux basics. I't sure that googling "linux newbie" will turn up several basic tutorials. If you're not willing to try a bit on your own, your Linux experience will be short and unhappy.