This study involvesthe numerical modeling of steady thermal radiation and chemical reaction on non‐Newtonian fluid motion via a bidirectional stretching surface. We have taken convective boundary conditions, and heat sources on the stretching surface. The working fluid of the present study is Casson fluid (“non‐Newtonian”) with couple stress. The self‐similarity forms of the nonlinear thermal radiative flow model are obtained by using similarity variables. Furthermore, the numerical results are computed with the help of fourth‐order Runge–Kutta–Fehlberg method with a shooting algorithm after reducing nonlinear partial differential equations have been translated into strong ordinary differential equations (ODEs). Impacts of the various flow physical parameters especially Biot number, nonlinear thermal radiation, and heat source parameters containing nonlinear ODEs are discussed in detail for distinct numerical values. A comparison of calculated results with the known numerical results made with the previously published literature is mentioned and obtained a good agreement. Finally, we found that the R
e
x
1
/
2
C
f
x $R{e}_{x}^{1/2}{C}_{fx}$ (“coefficient of skin friction”) declines along x
*
,0.35em
y
* $x* ,\,y* $ directions, respectively, with β $\beta $ via λ $\lambda $ while the opposite direction follows M $M$ with respect to λ $\lambda $ and the R
e
x
−
1
/
2
N
u
x $R{e}_{x}^{-1/2}N{u}_{x}$ (“heat transfer rate”), R
e
x
−
1
/
2
S
h $R{e}_{x}^{-1/2}Sh$ (“mass transfer rate”) increase with Γ $\Gamma $ via γ
1 ${\gamma }_{1}$ while opposite direction follows γ
1 ${\gamma }_{1}$ with respect to γ
2 ${\gamma }_{2}$.