Point-like singularities of black hole space–times in general theory of relativity (GR) and alternative theories of gravity are one of the controversial issues for decades. One way to remove the central singularity of the Schwarzschild black hole is the Kazakov–Solodukhin (KS) proposal, which takes into account the effects of quantum field theory within the GR framework leading to the KS black hole. On the other hand, the Event Horizon Telescope (EHT) becomes a noteworthy tool for constraining the black hole parameters in gravitational theories. Hence, in this work, we plan to study the null geodesic structure, shadow behavior, energy emission rate, and deflection angle of the KS black hole. Then, we constrain the quantum correction parameter of the KS black hole via EHT data of the M87∗ supermassive black hole. We observe that increasing the quantum effects in the KS black hole leads to amplification of the shadow size of the KS black hole.