Automatically setting new dates for recurrent events once the previous date has passed

Not saying I'll answer this but things to consider.
You'll need to specify start days/dates, for example

1. Once a month: Youd need a start day, e.g. you've put 20-09-2019 only because you know today is past the 20th of this month. So Excel would need to know that too, a start day e.g. 20
Also what happens if the once a month day is 29th 30th 31st - and today is the 1st of Febraury? There's no 30th of February so what date would you want then? Similar with other months like April June September and Novemeber and 31st of the month.

2. Once a week, again you'd need to specify a day of the week so Excel can tell when the next day occurs. Not difficult to work out.

3. Once a year, again a start date determine if that date has past or not.

4. Once every 3 mths, again a start date, prob use EDATE(), but again what if its the 29th of 30th or 31st of the month and the next 3mth date would be February?

But every 7 days starting when?
Or every 30 days starting when?

You cant know this

"the next due date would be March 1st."

without knowing this

"if my due date is Jan 31"

So 31st Jan would be your start date.
You need to supply some form of start date or start day depending on the frequency.

You cant just have the diagram youve supplied, you need to add additional info so Excel knows when the 7 or 30 days are up.

"The same day once a week"
Well when's that? Is it today, tomorrow, 3 days from now?
"It's every Tuesday"
Now I know and can work out the next Tuesday from todays date.
But I wouldnt be able to do that without knowing it was every Tuesday.
Thats what Im saying.

Get next day of week

A1+7-WEEKDAY(A1+7-B1)+1

where A1 is today's date and B1 is day number 0-7 starting with Sunday.