Set your own custom alert times in iPhone Calendar

When setting up alert times for an event in the IOS Calendar on iPhone there are only a few select options. 2 hours before the event is the furthest out you can set an alert that will happen the day of the event. I need it to be set to 3 hours. I want the alert 2 hours before I have to leave (1 hour drive) not 2 hours before the event. Why are there only a few options available with no customization? It’s 2019. Why isn’t this a standard option? It is on Android Calendar.