Believe me - you do not want "only one version of Perl".

Your system vendor supplies one version of Perl with the system. This version of Perl is what your system utilities use. Replacing that version of Perl with another version of Perl not supplied by your vendor will break your system.

Either you use whatever Perl your system vendor supplies you, or you create your own Perl, preferrably below /opt/perl.

If you don't believe me on how to configure and install your own Perl, I already pointed you to a more authoritative source than I am, the install instructions that come with the Perl source distribution. Of course, you are free to ignore both, my advice and the advice in the official documentation.