I use calendar events and put reminders depending on how important the task is. Like if it’s my mum’s birthday I put a reminder two weeks before (so I get her a gift) the day before and then the same day in the morning but if it’s something like remembering to call a company or something I just put one reminder at 3 pm on the day of the event.
You can then snooze the event for as long as you want until you have time to take care of it (at least on Samsung’s Android)