  The optical and ultra-violet broadband photometric and spectroscopic
observations of the Type II supernova (SN) 2016gfy are presented. The $V$-band
light curve (LC) shows a distinct plateau phase with a slope, $s_2$ $\sim$ 0.12
mag / 100 d and a duration of 90 $\pm$ 5 d. Detailed analysis of SN 2016gfy
provided a mean $\rm^{56}Ni$ mass of 0.033 $\pm$ 0.003 $\rm M_{\odot}$, a
progenitor radius of $\sim$ 350-700 $\rm R_{\odot}$, a progenitor mass of
$\sim$ 12-15 $\rm M_{\odot}$ and an explosion energy of 0.9-1.4$\rm \times
10^{51}\ erg\ s^{-1}$. The P-Cygni profile of H$\rm \alpha$ in the early phase
spectra ($\sim$ 11-21 d) shows a boxy emission. Assuming that this profile
arises from the interaction of the SN ejecta with the pre-existing
circumstellar material (CSM), it is inferred that the progenitor underwent a
recent episode (30-80 years prior to the explosion) of enhanced mass loss.
Numerical modeling suggests that the early LC peak is reproduced better with an
existing CSM of 0.15 $\rm M_{\odot}$ spread out to $\sim$ 70 AU. A late-plateau
bump is seen in the $VRI$ LCs during $\sim$ 50-95 d. This bump is explained as
a result of the CSM interaction and/or partial mixing of radioactive $\rm
^{56}Ni$ in the SN ejecta. Using strong-line diagnostics, a sub-solar oxygen
abundance is estimated for the supernova H II region (12 + log(O/H) = 8.50
$\pm$ 0.11), indicating an average metallicity for the host of a Type II SN. A
star formation rate of $\sim$ 8.5 $\rm M_{\odot}\ yr^{-1}$ is estimated for NGC
2276 using the archival $GALEX$ FUV data.
