I have learnt about the end of flash player, i.e. Adobe does no more support it.
As meany websites require flash-player, what can I do for replacing it ?
Long story short, you need to find alternative solutions for things that required Flash Player. This might mean finding new websites or games built on modern technology.
To that end, in order to give content developers plenty of time to remove dependencies on Flash Player, we announced in 2017 that Flash was going away at the end of 2020. Furthermore, most major browser vendors announced plans to drop support for browser plug-ins entirely around the same time.
Announcement, background and browser roadmaps:
Here's the consumer FAQ:
At this point, you should uninstall Flash Player. For convenience, links to the uninstallers follow.
Uninstall Flash Player - Mac:
Uninstall Flash Player - Windows:
Microsoft Update for Removal of Flash Player