The nature of Fermi surface in view of shapes and density of the nearest energy bands plays important role in tuning the physical and chemical properties of heavy fermions, Weyl metals, topological insulators, and superconductors. The interplay between superconductivity, magnetism, and fermionic nature of materials can be enhanced by modifying the shape of Fermi surface. The modification may be accomplished by tuning the surface topology, such as flatness and thickness, of electronic energy bands around the Fermi surface. Herein, we investigate the interplay between the magnetism, superconductivity, and heavy Fermionic nature of PrSb by tuning the shape of the Fermi surface by Sn substitution via PrSnxSb1-x (x = 0.0,0.25,0.50,0.75 &1.0) substitution scheme. For the theoretical designing of the materials and computation of the targeted properties, we implement density functional theory using the generalized–gradient approximation extended to the Perdew-Bruke-Ernzerhof correction to account for the exchange–correlation. The modification in the thickness and flatness of energy bands and density of states around the Fermi surface of PrSb compounds by changing the Sn/Pb substitution ratio, leads to simultaneous enhancement of the interplay between magnetism, superconductivity, and fermionic nature of the compounds.