the system is already running a relatively competent 6700 variant...
(Unless , and even if, HP's support page specifically lists compatibility for a 6700K, it's possible the existing power delivery and or thermal solution would be inadequate for even that upgrade...; you can weigh the cost vice simply upgrading to a 10400/11400 or a B550/R5-5600X...which will likely need a new case, PSU, and RAM as well)