If you want to support Unicode (which many users expect these days), you'll need to learn a bit about it, and how perl deals with it. Perl includes a fine manual:

• https://perldoc.perl.org/perluniintro
• https://perldoc.perl.org/perlunitut
• https://perldoc.perl.org/perlunicode

We also have frequent discussions about it here in the monastery archives.

On the other hand, if that seems like an unpleasant amount of learning for the moment, and you want Unicode to just go away so you can get back to work, you might find Text::Unidecode useful.