The electron configuration for iron, $Fe$ is $1s^2 2s^2 2p^6 3s^2 3p^6 3d^6 4s^2$
The orbital filling order for $Fe$ is $1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^6$
Iron does not occur as $Fe_2$ in nature. It is not a diatomic element.
The ion $Fe^(2+)$ electron configuration is $1s^2 2s^2 2p^6 3s^2 3p^6 3d^6$.
It is missing the two in the $4s^2$ orbital. This makes the ion a cation, an ion that is positively charged because it has lost .