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Blazars are known to emit exceptionally variable non-thermal emission overthe wide range (from radio to $\gamma$-rays) of electromagnetic spectrum. Wepresent here the results of our $\gamma$-ray flux and spectral variabilitystudy of the blazar Ton 599, which has been recently observed in the$\gamma$-ray flaring state. Using 0.1$-$300 GeV $\gamma$-ray data from the$\it{Fermi}$ Gamma-ray Space Telescope (hereinafter $\it{Fermi}$), we generatedone-day binned light curve of Ton 599 for a period of about one-year from MJD59,093 to MJD 59,457. During this one year period, the maximum $\gamma$-rayflux detected was 2.24 $\pm$ 0.25 $\times$ $10^{-6}$ ph cm$^{-2}$ s$^{-1}$ atMJD 59,399.50. We identified three different flux states, namely, epoch A(quiescent), epoch B (pre-flare) and epoch C (main-flare). For each epoch, wecalculated the $\gamma$-ray flux variability amplitude (F$_{var}$) and foundthat the source showed largest flux variations in epoch C with F$_{var} \sim$35%. We modelled the $\gamma$-ray spectra for each epoch and found that theLog-parabola model adequately describes the $\gamma$-ray spectra for all thethree epochs. We estimated the size of the $\gamma$-ray emitting region as 1.03$\times$ $10^{16}$ cm and determined that the origin of $\gamma$-ray radiation,during the main-flare, could be outside of the broad line region.

$\gamma$-ray Flux and Spectral Variability of Blazar Ton 599 during Its 2021 Flare