A quick hunt online suggests trying Dolphin Browser Beta(link goes to Google Play Store)]] There is a non beta version but that does not mention Flash. So that may be something they are trying out in the beta version. Kindle Fire is not listed in the tested devices list, so it may or may not work.
Don't think you can. Most Android devices allow you to install third party apps which means you can still get Flash player even though it's not officially supported by Google Play. However, I think the Kindle Fires are locked to the Amazon store, meaning you can't install anything 3rd party (there might be a hack I don't know about of course!)
An e-magazine I get sent to my Yahoo account tells me I need Adobe Flash Player to see one of the articles on my kindle fire but when I press the button to download it, it asks me which version I want and so on. Think I tried this before and possibly discovered you can't get it for kindle fire or something...
Does anyone know whether a. you can get flash player for the kindle fire HD and b. if so, how?