Several projects w/ Excel involving dates ...
 

I'm teaching myself on using the date function. There are several things I want to do w/ this project.
1. Create a spreadsheet listing all user's
2. Execute a trigger date of every 30 days to notify user's to change their passwords by automatically sending out an email.
3. Once the date is passed, a new trigger date will follow (reoccurance)

I've looked at various resources on getting started but I don't know which formula to use. I just know the basics and trying on my own to figure it out. Does anyone know how to get started or can point me in the right direction?

Thank you