Originally Posted by Adelphos

If you are flying into a country where you have to self quarantine, ideally immigration authorities will inform you of that requirement, and you will likely have to pay for lodging/ If you cannot afford to pay for lodging to self quarantine yourself, you either have to be transported to a hospital or some other kind of public accommodation or put back on a plane to your original country of origin.

This is why international travel at this moment is kind of risky - too many unanticipated costs that may be imposed on the traveler