Due to the outstanding electrical and physical properties of two-dimensional Nitrogenated Holey Graphene (C2N) based sensors, they have become increasingly important. In comparison to other solid-state sensors, C2N-based sensors are very sensitive, stable, and responsive. The conductivity of C2N changes when exposed to a wide range of organic and inorganic substances. Different target molecules are being detected using this change in electrical conductivity as a detection signal. With first-principles transport simulation, a sensor device built from Nitrogenated Holey Graphene (C2N) sensor is designed for DNA nucleotides detection. The transverse currents of this sensor can be used to discriminate between the four DNA nucleotides. A C2N-based sensor is simulated in this article using Quantumwise Atomistix Toolkit (ATK), a simulator for nanoscale semiconductor devices. Calculations have been made to determine how the work function, density of state, and electric current vary when target molecules are present. To increase the sensor's selectivity and accuracy, the current has been considered as a detecting mechanism. When target molecules are present, the change in work function and the electric current can both be used as detection signals.