The period in which the first element is located can give you an idea of the energy levels of its electrons. Elements in the same period generally have the same number of electron shells.
The group or column in which the first element is found indicates the number of valence electrons it has. Elements in the same group often exhibit similar chemical properties due to having the same number of valence electrons. The period of the second element can also give information about its electron configuration and energy levels.
The group of the second element can indicate its valence electron configuration. Elements in the same group tend to have similar outer electron configurations.