Cannot send email using shield auth

Hi, I have implemented CodeIgniter Shield for my Project, and been trying to register with email verification, but some how 
this message pops up:
CodeIgniter\Shield\Exceptions\RuntimeException

Cannot send email for user: [email protected]
Unable to send email using PHP mail(). Your server might not be configured to send mail using this method.
is this problem caused by Shield or by a mistake on my pc's side?

I'm using latest codeigniter version which is 4.2.10 and php 8.0.23

thanks