Flash Player will not install on a brand new iMac

Computer:

1 x brand new iMac (bought 1 week ago): OS X 10.11.6

3.3 GHz Intel Core i7

16 GB memory

Adobe Flash version:

Version 22.0.0.209 (17,7 MB)

Downloaded, extracted and once double clicked on 'Install Adobe Flash Player', I confirm I wish to continue and input my password and update my Player Preferences, immediately a screen appears telling me that the installation has failed due to 'Not enough permissions t ...'

Any clues as to why this is happening and how to fix it out would be very welcome.

Thank you very much.