The First Day of month function is created as Power Apps named Formula for getting a first day of a month by provided input date.
Formula Code
FirstDayOfMonth(inputDate:Date):Date = DateAdd(
inputDate,
1 - Day(inputDate),
TimeUnit.Days
);
Eye on Detail
Mostly, we play with Date functions in Power Apps. This function helps you to find the first day of month of the provided input date.
Demo