  This paper explains the significance of neutrino mass in the cosmic
progression from the radiation-dominated phase to matter and subsequently to
the dark energy-dominated era. We have put a constraint on the total mass of
neutrinos by coupling them with quintessence. For the combination of full
data(Pantheon+CMB+BAO+CC), we find $ \sum m_{\nu}<0.101$eV \ \ (95$\% $CL.) and
for the relativistic to non-relativistic phase transition redshif ${z_{\rm nr}}
= 180$ which is in the matter-dominated era. Our findings confirm that when
neutrinos become non-relativistic, the universe transitions from a
radiation-dominated era to a matter-dominated era. Coupled neutrinos with
quintessence (CQ) have also a significant impact on transitions from a
matter-dominated era to a dark energy era. We have shown this effect by
investigating the impact of neutrino mass on the bulk flow direction and
amplitude of bulk velocity. Moreover, we have discussed the impact of this
coupling on the CMB power spectrum to show the anisotropy in the universe.
Finally, we have established a link between the quintessence field coupled with
neutrinos and the bulk flow, which allowed us to demonstrate that the mass of
neutrinos could be the cause of anisotropy in the universe.
