You can create a query that has a field showing the number of days between two dates (today and your target date). I cover this in Access Expert 27 and 28.

NumDays: Date()-[TargetDateField]

You can then set up criteria to show you records that are >=15 or >=30 days old. Query Criteria.

As far as a prompt goes, you could use a startup event, perhaps the OnOpen event for your Main Menu Form which could do a DLOOKUP and see if there are any records that meet that criteria, and then MsgBox you. It's a bit of work, but it's not super difficult if you know a little programming. I cover popup notifications for reminders in my DateTime Seminar.

Good Morning Richard for the information.  I am actually learning as I go so I am not good with coding as yet.  I will try to make do with what I am learning from your beginner course to create my database.

In Access Beginner Level 1 I show you how to create query criteria. Just add your date field to a query, and for the criteria put:

<=Date()-15

That will show you all records that are older than 15 days. Make another query for 30 days. You'll have to run them manually every day, but it gets the job done. Later, when you learn more advanced techniques, it will get easier.