To play the file with the SWF extension you need Adobe Flash Player. The official adobe site has deleted its flash archive, but you can download it here from the internet archive.
For Windows - https://archive.org/download/flashplayer_32_sa_202104/flashplayer_32_sa.exe
For Linux - https://archive.org/download/flashplayer_32_sa_202104/flash_player_sa_linux.x86_64.tar.gz
Just open the SWF file in the downloaded player. There are no viruses.