I’m looking for an older version of quartus,
exactly quartus II 9.0 web edition to modify an old project based on a flex EPFK10K50.
There is a way to download it?
QuartusII 13.0sp1 is the earliest version now still available online.
Not even the internet archive wayback machine will work, as it did not cache contents of files, only web pages.
So unless you know somebody that knows somebody that has a secret archive you are out of luck.