click start/performance and maintenance/system/advanced/start up and recovery/settings
untick "time to display list of operating systems" apply and ok.
note if you have the recovery console installed this will not be displayed anymore as it shows here as an option if installed. but if you ever need it you can go back to the above and retick via safe mode if you cannot get windows to start normally.
if that was ever the case though i would just re install though rather than faffing about with it.