Is the regular covid test good for a flight or needs a special one?

Dont think you need one at all. Even for the airlines. You do have tonwear a mask that covers your nose and mouth.

We recently travelled overseas, we had to get tested, for travellers. It's called a PCR test.

I had to have a Covid test to get back in the US from Guatemala and it was a rapid test. Going the other way it had to come from the health department.

Covid test (PT-RCP) is required depending on your destination,especially if international flight. Please check advisory on your airline and destination.