Setting up alerts in Excel

I have a client who runs all her projects in OneDrive using Excel as her project scheduling tool. She has about 12 projects running concurrently and is therefore missing deadlines.

Is there a way to set up alerts in Excel that can send an email or similar to the resources that their deadline is due? Maybe a macro or something?

It makes life simpler if everything is in one place. She uses Avaza as a time management tool and not a scheduling tool.