Reminder for call, related to a customer or any entity

Hello is there a good way to generate a reminder, thats first pop ups on given time.

It should be like an todo, or planned communication. for example if a customer buys one Product, and i want to che in 10 months if he wants to buy more , or extend the warranty.

You could use a “ToDo” but I guess that’s not quite what you want because that will stay there until it’s done and not just pop-up later. So I guess that’s something that needs to be implemented as a “Reminder” DocType.