In recent year, ferroelectric oxides are getting tremendous attention in the both research and technological aspect due to various interesting phenomena exhibited by them, such as electrocaloric (EC), photovoltaic (PV), photostriction, photo-ferroelectric effect, etc. In this regard, exploring the multifunctional characteristics of ferroelectric materials is crucial for the detailed understanding of the dynamics associated with these phenomena and implement these characteristics to the application perspective. Consequently, in making next-generation PV devices, it is essential to understand the mechanism of the above bandgap PV response observed in the ferroelectric systems. Thereby, in the present work, a combined experimental and theoretical studies are carried out on the BaTiO3 (BTO)-based ferroelectric oxides exhibiting enhanced ferroelectric characteristics. The observed anomalous PV response in the materials suggests that the origin of the effect is due to the simultaneous outcome of ferroelectric polarization and the band topol ogy near the conduction band minima. Furthermore, the significant change perceived in the photo-induced dielectric and ferroelectric properties proves the influence of the ferroelectric order parameter by the light as an external stimulus. The observed effect illustrates the potentiality of the ferroelectric materials in optoelectronic devices. Additionally, the enhanced and tunable EC characteristics are achieved by designing the ferroelectric materials through lattice site engineering on the parent BTO sample. The demonstrated EC effect on site-engineered BTO samples reveals the application potential in environment-friendly solid-state cooling devices. Overall, the work provides insight into understanding the fundamental physics behind the intriguing ferroelectric characteristics towards the development of advanced electronic devices.