Is showing a finger to a driver who proposed marriage, in order to determine the ring size, considered zina, and what is its expiation if so?

Repentance must involve regretting what has passed and resolving not to return to it. There is no specific expiation for this act, but good deeds such as prayer and charity atone for sins. The Prophet, may Allah’s prayers and peace be upon him, recited to a man who had erred Allah’s saying: "Establish prayer at the two ends of the day and in the first hours of the night. Indeed, good deeds do away with evil deeds. That is a reminder for those who remember," and he said that this is not exclusive to him but for all people. This act is not actual fornication (zina) that necessitates the prescribed punishment (hadd), but rather it is one of the preludes to fornication, like looking and talking. It is stated in the Hadith (definition): "Indeed, Allah has decreed upon the son of Adam his share of zina, and he will inevitably realize that. The zina of the eye is looking, the zina of the tongue is speaking, the soul wishes and desires, and the private parts confirm or deny that."