Calcultaing number of days between given dates

Hi SS Team,

I want to calculate the number of days between two given dates, say 12/08/2020 and 13/10/2020. can someone please help with the syntax to use or an example of the same?

Thanks

See here:

Thank you @sergiy for your always quick response.

Appreciated. Let me have a look and in case I have further questions, will revert.