Can't Use Adobe Flash or get it on Windows 10

trying to use www.speedtest.net  messages says I don't have adobe flash, when I try to download adobe flash, i always getting a message blocking me, saying it not necessary as it is built into Microsoft Edge.  Windows 10 doesn't list in to uninstall, So I can't use it, it says its there, I can't uninstall, I can install it.  So How do I use it?