Yes. You can use Google Pay even if you do not own any debit card by using a GPay card. GPay offers an official GPay card that you can buy from grocery stores and in the Google Pay online store. This card can be used like a regular debit card. And, if you do not want to buy the GPay card, you can use a different virtual card that you can obtain from PayPal, Skrill, Gcash, and more.