Nanoparticles are used in industrial and engineering by allowing for faster heat transfer rates in microchips, vehicle cooling, food processing, and nuclear reactors. This research aims to scrutinize the three-dimensional bioconvectional flow performances of viscoelastic nanofluids through a elongating sheet with motile microorganisms. Radiative impact and solutal boundary conditions are studied here. The impacts of thermophoresis, Brownian motion, and bioconvection are also considered. By using suitable similarity transformations, the PDEs are converted into ODEs. The numerical and graphical results are calculated with the help of shooting scheme built-in function Bvp4c in computational tool MATLAB. The graphical and numerical importance of physical engineering parameters like local skin friction, local Nusselt, local Sherwood, and local motile microorganism numbers are discussed here. The thermal profile is enhanced for the higher estimations of the Brownian motion and thermophoresis parameter. The heat profile is boosted up for the increasing variations of the thermal radiation and the thermophoresis parameter. The energy profile is improved by increasing the estimations of solutal Biot number while declining for mixed convection parameter and unsteadiness parameter. The microorganism profile decays for Peclet and bioconvection Lewis number while rising for buoyancy ratio parameter and bioconvection Rayleigh number.