The package, called NTP-ERSN (N eutron T ransport P ackage from the R adiations and N uclear S ystems G roup), is an open-source code written in FORTRAN90 for a pedagogical purpose to solve the steady-state multigroup neutron transport equation. This package is based on three classical methods, namely the collision probability (CP) method, the discrete ordinates (SN) method and the method of characteristics (MOC). These methods are employed to obtain scalar and angular flux distributions in homogeneous and heterogeneous slab geometry with isotropic and anisotropic scattering. The source code algorithms are very simple to be comprehensive by engineering students. In addition, NTP-ERSN is a simple framework to add and test new algorithms. On the other hand, a graphical user interface written in Python programing language has been developed to simplify the use of NTP-ERSN. Numerical results are given to illustrate the NTP-ERSN code's accuracy. Finally, the present software can be useful as an academic tool for teaching reactor physics. It is freely available for download on GitHub (https://github.com/mohamedlahdour/NTP-ERSN).