Present study concerned with the theoretical work with numerical investigation of MHD transient naturally convective and higher order chemically reactive viscoelastic fluid with nano-particle flow through a vertical porous stretching sheet with the effects of heat generation and radiation absorption. A boundary layer approximation is carried out to develop a flow model representing time dependent momentum, energy, and concentration equations. The governing model equations in partial differential equations (PDEs) form were transformed into a set of nonlinear ordinary differential equation (ODEs) by using non-similar technique. Explicit Finite Difference Method (EFDM) was employed by implementing an algorithm in Compaq Visual Fortran 6.6a to solve the obtained set of nonlinear coupled ODEs. For optimizing the system parameter and accuracy of the system, the stability and convergence analysis (SCA) was carried out. It was observed that with initial boundary conditions, the system converged at Prandtl number>= 0.253 and Lewis number >=0.16. The velocity, temperature and concentration flow are investigated and shown graphically with the effect of system parameters and numerical comparison.