Whenever you run root operations, such as apt-get
, you absolutely must use sudo
. Otherwise, you will get the "Permission Denied" error. The message even hints at what you should be trying: "Are you root?"
Use sudo apt-get install flashplayer
to install that package.
As Pilot6 has pointed out in the comments, you need pepperflash
for Chromium. However, the package name he gave you was not correct. You want:
sudo apt-get install pepperflashplugin-nonfree
That will install Flash Player for Chromium (and I believe Firefox). It will start working either after you restart Chromium or reboot the computer.
If it doesn't, run
sudo update-pepperflashplugin-nonfree --install
to manually install it to Chromium.
sudo apt-get install flashplugin-installer
.sudo apt install adobe-flashplugin
. Restart the browser after you do it.