The second half of the question is: Can I give food to fasting people who are travelling in cars and trains before the adhaan, or must the food actually reach poor and needy people? Because I do not know how to find 120 poor people in order to feed them.
The one who has intercourse with his wife during the day in Ramadaan has to free a believing slave. If that is not possible then he must fast for two consecutive months. If he is unable to do that, then he must feed sixty poor persons. The expiation is required in this order and it is not permissible to move from one to the next unless one is unable to do the first thing. This order was stated by the majority of scholars. So it is not permissible for you to turn away from fasting to feeding the poor if you are able to fast. If you are able to fast then you must do that.
If you are unable to fast, then you must both feed sixty poor persons. It is essential that the people to whom you give food be in need.
Based on that, it is not permissible to give food to people who are travelling in the manner you describe, because you do not know whether they are poor or not.
But if you give food to one who appears outwardly to be poor, there is nothing wrong with that, but if you give it to anyone who is travelling, that is not permissible.
If you cannot find any poor people, then you can delegate one of the trustworthy charitable organizations or the imam of a mosque to do that on your behalf, or you can ask your friends to help you find poor people.
We ask Allaah to accept your repentance.
And Allaah knows best.