There isn't a way for one event to delete other events, through event commands.
Normally you'd just turn on a switch at the appropriate time, and give all the events you want "deleted" a second page with no sprite, which is conditioned by that switch.
The only other way is via script calls, which is not the same from engine to engine, so if you want to do it that way, you need to be specific about what engine you're using (you posted in MV support, but your comment makes me wonder if you're not using something else)