Monkeypox (MPX), which is similar to smallpox and cowpox, is caused by the MPX virus. It primarily appears in isolated areas in Central and West Africa, often near tropical rainforests. In this paper, a mathematical model of the MPX virus is explored and the sensitivity of the reproduction number is investigated. Two different numerical techniques, forward Euler, and nonstandard finite difference (NSFD) are constructed for solving the studied model numerically. The convergence, positivity, boundedness, and consistency of the NSFD scheme are investigated. The simulated graphs are displayed to illustrate the main attributes of the developed methodologies. The simulation results indicate that the NSFD scheme demonstrates unconditional convergence, whereas the convergence of the other two techniques is contingent upon the values of the step sizes.