  We carried a detailed temporal and spectral study of the BL\,Lac by using the
long-term \emph{Fermi}-LAT and \emph{Swift}-XRT/UVOT observations, during the
period MJD\,59000-59943. The daily-binned $\gamma$-ray light curve displays a
maximum flux of $1.74\pm 0.09\times 10^{-5} \rm ph\,cm^{-2}\,s^{-1}$ on
MJD\,59868, which is the highest daily $\gamma$-ray flux observed from BL\,Lac.
The $\gamma$-ray variability is characterised by power-spectral-density (PSD),
r.m.s-flux relation and flux-distribution study. We find that power-law model
fits the PSD with index $\sim 1$, which suggest for long memory process at
work. The observed r.m.s.-flux relation exhibits a linear trend, which
indicates that the $\gamma$-ray flux distribution follows a log-normal
distribution. The skewness/Anderson-Darling test and histogram-fit reject the
normality of flux distribution, and instead suggest that the flux distribution
is log-normal distribution. The fractional-variability amplitude shows that
source is more variable in X-ray band than in optical/UV/$\gamma$-ray bands. In
order to obtain an insight into the underlying physical process, we extracted
broadband spectra from different time periods of the lightcurve. The broadband
spectra are statistically fitted with the convolved one-zone leptonic model
with different forms of the particle energy distribution. We found that
spectral energy distribution during different flux states can be reproduced
well with the synchrotron, synchrotron-self-Compton and external-Compton
emissions from a broken power-law electron distribution, ensuring equipartition
condition. A comparison between the best fit physical parameters show that the
variation in different flux-states are mostly related to increase in the
bulk-Lorentz factor and spectral hardening of the particle distribution.
