even if you have a debit card, in much of the world unless it’s a visa/mastercard it’s not going to be accepted in many places online

my debit card (in canada) uses interac. it’s accepted basically everywhere in physical stores, but online it’s pretty much useless if you don’t also have paypal (which is also not accepted everywhere a credit card would be)

Those have fees, though. Back when I didn't have a bank account, it was already over $5 per card, so I assume it's much higher 15 years later.