What is the ruling on incentives provided by delivery companies to drivers, which include guaranteeing a certain amount or a bonus upon fulfilling specific conditions, and is the driver sinful for taking them?

There is no objection to the driver accepting company incentives, whether they are in the form of increased profits or by paying the difference if they fall below a certain amount. There is no Sharia prohibition on the company committing to these rewards, and the fact that they are unknown in the first type does not prevent their permissibility, because gifting an unknown item is permissible according to the most authoritative opinions of the scholars.