The RENO experiment reports measured flux and energy spectrum of reactor electron antineutrinos,($overline{ u}_e$) from the six reactors at Hanbit Nuclear Power Plant. The measurements use 966,094,(116,111),$overline{ u}_e$ candidate events with a background fraction of 2.39%,(5.13%), acquired in the near,(far) detector, from August 2011 to March 2020. The inverse beta decay (IBD) yield is measured as (5.852$,pm,$0.124$) times 10^{-43}$,cm$^2$/fission, corresponding to 0.941,$pm$ 0.019 of the prediction by the Huber and Mueller (HM) model. A reactor $overline{ u}_e$ spectrum is obtained by unfolding a measured IBD prompt spectrum. The obtained neutrino spectrum shows a clear excess around 6,MeV relative to the HM prediction. The obtained reactor $overline{ u}_e$ spectrum will be useful for understanding unknown neutrino properties and reactor models. The observed discrepancies suggest the next round of precision measurements and modification of the current reactor $overline{ u}_e$ models.
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