This paper explores the shadow and greybody bounding characteristics of a regular scale-dependent black hole (RSDBH) in 4-dimensional spacetime. The focus is on determining constraints for the parameter $\epsilon$, which describes the scale-dependent solution relative to the classical observed shadow radius $R_{\text{sh}}$. Using data from the Event Horizon Telescope (EHT), the authors find that there is a unique value for $\epsilon$ corresponding to the mean of $R_{\text{sh}}$, with uncertainties possibly due to fluctuations in the scale-dependent parameter. For Sgr. A*, $\epsilon > 0$ is positive, while for M87*, $\epsilon < 0$. The study also examines the shadow radius and weak deflection angle within specified constraints, noting discrepancies in both the shadow and deflection angle, especially near the critical impact parameter. Additionally, the paper analyzes the greybody factors for scalar fields and photons emitted by RSDBHs, finding that as $\epsilon$ increases, the bounds for the greybody factor also increase, indicating favorable barrier properties. The results provide insights into the quantum effects on classical backgrounds and suggest further research directions, such as studying optical properties with more realistic features.This paper explores the shadow and greybody bounding characteristics of a regular scale-dependent black hole (RSDBH) in 4-dimensional spacetime. The focus is on determining constraints for the parameter $\epsilon$, which describes the scale-dependent solution relative to the classical observed shadow radius $R_{\text{sh}}$. Using data from the Event Horizon Telescope (EHT), the authors find that there is a unique value for $\epsilon$ corresponding to the mean of $R_{\text{sh}}$, with uncertainties possibly due to fluctuations in the scale-dependent parameter. For Sgr. A*, $\epsilon > 0$ is positive, while for M87*, $\epsilon < 0$. The study also examines the shadow radius and weak deflection angle within specified constraints, noting discrepancies in both the shadow and deflection angle, especially near the critical impact parameter. Additionally, the paper analyzes the greybody factors for scalar fields and photons emitted by RSDBHs, finding that as $\epsilon$ increases, the bounds for the greybody factor also increase, indicating favorable barrier properties. The results provide insights into the quantum effects on classical backgrounds and suggest further research directions, such as studying optical properties with more realistic features.