Making a 7-hour timer-based relay I want to make a very small 7-hour timer circuit that can turn on a relay after 7 hours. I am trying to make the first prototype with an Arduino Nano but I can't understand how to program it for such purpose. So please help me out.

Once I make a prototype in Arduino then I was thinking to make a small one  using an ATtiny13. Can I use an ATtiny13 for such purpose?
cant understand how to program it for such purpose so please help me out


it is fairly easy to approach such questions:

1) you can program any?

2) can you program this mcu to blink an led?

3) can you program this mcu to do short time counting?

4) can you program this mcu to do long time counting?

what you help helps you the most depends on your  answers to those questions.