what does the Bas/Esp light mean and what do i do

my scanner shows codes po 121 po161 po 400 po 141 it doesnt throttle up untill peddle is 1/4 way down then races up to high rpm

po121 n/a in all data po161 left 02 sensor heater issues po400 egr issues po141 rt o2 heater issues. seek proper diag and repair as this will get exp if you start repl parts at will