Navigate to the Settings menu and then click on the Payments tab to access Add Payment Method.

Settings > Payments > Add Payment Method

When you click on Add Payment Method, it will open a modal box. Choose PayPal. Enter your PayPal account Email, choose a suitable Button Color for PayPal button, and then click on Add.

Confirm PayPal has been added

Open your store page, add any item to your shopping cart and continue with checkout. There you should see PayPal as an available option for payment.