Dicalcium nitride (Ca2N) is a two-dimensional (2D) electride with unique electronic behavior. In this study, we use pseudoatomic orbital (PAO) basis sets to investigate its electronic and optical properties. This methodology 
provides an accurate representation of the electronic structure associated with the interlayer and surface anionic states of the Ca2N bilayer, enabling a comprehensive study of its optical properties. We identify several peaks 
in the dielectric functions which correspond to interband transitions. Our analysis of the optical conductivity and linear optical spectra, derived from these dielectric functions, reveals distinct peaks in the linear optical 
spectra of both bulk and bilayer Ca2N. These peaks are influenced by the in-plane and out-of-plane vectors. This investigation provides valuable insights into the interband transitions and optical behavior of this intriguing 2D electride. It also lays the foundation for future studies of promising 2D electrides.