Junk emails offering downloads?

Yeah, this is totally fake.  Good job not getting tricked!

If you're running a modern operating system and browser, the technological controls that prevent malware installation are pretty good.  Attackers focus on the path of least resistance, which means that humans are increasingly targeted as the weak link.

Where possible, use your operating system's app store to download and update software.  If it's not available in the app store, either go to the developer's website directly by typing the address in the browser, or use a trusted search engine to find the link.  Never click through from a pop-up or email link. 

For Flash Player, it's not available through the app store, so always download it from here:
https://get.adobe.com/flashplayer/

Once installed, set it to update automatically.  At that point, just consider any update prompts or notifications as fake and ignore them.

Also, some browsers include Flash Player as a built-in component, and updates and installation are automatically managed.  Chrome includes Flash Player, and handles updates through it's regular update manager.  On Windows 8 and higher, Microsoft Edge and Internet Explorer 11 include Flash Player as a built-in component, and updates are handled through Windows Update.

Not real. Not install... If you need update your Flash Player go website Adobe and update