You simply have to check in which directory it's installed.

Core modules bundled with Perl:

$ perl -V:'install(privlib|archlib)'
installarchlib='/.../lib/5.36.0/x86_64-linux-thread-multi';
installprivlib='/.../lib/5.36.0';
[download]

Installed by user:

$ perl -V:'installsite(lib|arch)'
installsitearch='/.../lib/site_perl/5.36.0/x86_64-linux-thread-multi';
installsitelib='/.../lib/site_perl/5.36.0';
[download]

You might find a module in both if you upgraded a core module.