What is the specific distance in meters between the Imam and the first row of congregants, what is the ruling on the prayer of one for whom the distance was long, and is it permissible for the distance to vary between the first and second rows?

There is no sacred text that specifies the distance between rows in measurements, but there is a command to draw the rows close together, as the Prophet, may Allah’s peace and blessings be upon him, said: “Straighten your rows, draw them close together, and align your necks.” The intention behind drawing them close together is that there should not be a distance between two rows that could accommodate another row. A long distance between rows does not invalidate the prayer, nor is the prayer invalidated if the distance between the Imam and the first row differs from the distance between the other rows.