Flash Player is not officially supported on any Windows Server, though installation isn't blocked. Essentially, we don't code, nor test for it, so there's no guarantee on how it'll function on Windows Server.
MS doesn't publish anymore and could find in the Adobe website. I wonder what is the best way to secure my flash component in IE 11 browser and below.
Are you looking for the SCCM/SCUP/CUPT packages? If so, they're available via Flash Player distribution license (free for the vast majority of use cases). To request a distribution license go to Adobe Flash Player Distribution | Adobe Most requests are approved almost immediately, but can take up to 2-3 business days. Once approved, you'll receive an email with the link to the distribution download page to download the files.