For reading the CSV files you can create an Integration project and use the Separated Values Generator. Once you choose your CSV file it creates components that allow you to read/write the CSV. It will also create a data type with your field names. The components take a FileDataType so you can combine this with the ReadFile component.
To create the email content there are many options. For simple plain text you can use the For Each Element in Collection component in conjunction with Merge Text component to build a string that has all of the groups/people from the collection. Then merge this into the rest of the email text in Send Email or Send Email via SMTP.
If you want to do this daily without any user input look at Monitoring project type. You can set a schedule and the project will run automatically. Otherwise, if its invoked by user input you could use Web Forms project type.
Good luck!