JUNO is a multi-purpose neutrino observatory under construction in China. It will host a $20~\mathrm{kt}$ liquid scintillator detector underground with an overburden of $650~\mathrm{m}$ to study the neutrinos from different neutrino sources. With an unprecedented energy resolution of $\sim 3\%$ at $1~\mathrm{MeV}$, JUNO is designed mainly to detect the anti-neutrinos from the nuclear power plants located $\approx 53~\mathrm{km}$ from the detector. One of the main physics goals of the experiment is to determine the neutrino mass ordering and to precisely measure the neutrino oscillation parameters $\Delta m^2_{21}$, $\sin^2\theta_{12}$, and $\Delta m^2_{31}$ using the reactor anti-neutrino flux. The results from JUNO are expected to improve upon the existing knowledge of precision on these three parameters by almost one order of magnitude. Additionally, JUNO can also detect solar and atmospheric neutrinos, and the neutrinos from supernova explosion. It will also search for a wide range of physics including the study of proton lifetimes, indirect dark matter searches, Geo-neutrinos, etc. This contribution will mainly report on the physics of neutrino oscillations with the reactor neutrinos, and discuss the analysis strategy used to treat the various uncertainties and backgrounds in estimating these parameter sensitivities.