Yes, basically all you need is a PayPal account. The documentation¹ provided by PayPal is rather clear, so I suggest you first read up on that, before looking at the Perl modules.

In a nutshell: Your customer makes a payment, PayPal's server posts the data to your script, your script checks it and returns the data to PayPal.

A nice thing is that you can test this in the PayPal sandbox²

You have to have more than a PayPal account: you have to confirm your email address. When you set up your account, PayPal sent an email to the address you used. That email contains a link to PayPal. When you access that link, PayPal knows the email got to you and that your email address works. From the PayPal help section: How do I confirm my email address? and Getting Started - Email Confirmation.

When you view your account in PayPal, it shows you your primary email address. Follow that link and PayPal shows you all of the email addresses you have associated with your account. Unconfirmed addresses have an "(Unconfirmed)" under them. If your address unconfirmed, you can select it and choose the "Confirm" submit button, which sends you the confirmation email that has the link you need.