A crucial aspect of nanotechnology is the creation of biologically driven methods for environmentally friendly synthesis of nanoparticles. In this research article, we show a green and biogenic approach to synthesizing metal nanoparticles by using plant extract. Iron nanoparticles have been synthesized by processing anhydrous ferric chloride with an extract from F. religiosa leaves. In this process, the extract from F. religiosa leaves serves as a reducing agent as well as a capping agent. Solutions have been prepared in the proper concentration and used with the proper procedure and time to make Ficus religiosa-iron nanoparticles (FRFeNPs). Stirring time, temperature, and rpm have been carefully maintained throughout the process as they have significantly influenced the properties of the nanoparticles. First confirmation comes from colour change during the reaction which indicate the production of FRFeNPs. Again, confirmation of iron nanoparticles formation during the reaction has been established by the UV-Vis Spectrograph showing peak at 450 nm. The synthesized FRFeNPs have been further characterized using different instruments, including a FTIR Spectroscopy, FESEM-EDX, XRD, and DLS. Antibacterial activity of iron nanoparticles has been assessed using the well-diffusion method. FRFeNPs tested against both gram +ve & -ve bacteria i.e. Pseudomonas fluorescens, E. coli, S. aureus, and B. subtilis, respectively. Significant activity of the FRFeNPs was demonstrated by antimicrobial activity.