Flash is no longer being developed for Linux, and the newest versions are only available built-in to Chrome. If you use the Chromium browser, you can extract the Flash plugin from Chrome and use it. If you use Firefox, you'll need to...
Method 2 of 3:
Chrome
Update Chrome. Flash is built-in to Chrome, and no extra effort is required to get it running. Simply keep Chrome up to date and Flash should work just fine.Method 3 of 3:
Firefox
Change browsers to Chrome or Chromium. Adobe is no longer supporting Linux development outside of the Pepper Flash plugin for Chrome. That means that the Flash plugin for Firefox is very outdated and is not receiving any improvements and only minor security patches.
Click CTRL + ALT + T at the same time- OR press "Super" key (windows key) and type in "Terminal." Launch it "Terminal". You should see a terminal.

Type "sudo apt-get install flashplugin-installer"

Type in your administrative password for sudo. You cannot view asterisks on the screen, but you're still typing it.

Install the plugin by pressing "Y" (yes) on Terminal.

Restart Firefox for the new plugin to take effect.
Update 04 March 2020
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