how to change hour start date and end date
You can use "startDate" to change the visible date range: https://doc.daypilot.org/calendar/manual-date-switching/
The end date is calculated automatically, depending on the viewType value (https://doc.daypilot.org/calendar/view-types/). For viewType="Week", viewType="WorkWeek", and viewType="Day" it will match the selected range. For viewType="Days" it will use add the value of "days" property to the "startDate".