@CP0822
Yes, calculated columns will be available for your data table. However, I would consider using a Gallery if possible over a DataTable because the DataTable is NOT going to see your calculate as a Date properly and you will end up with a ISO representation of your Date rather than a formatted date. You can control this better in a Gallery.
If you are not seeing your calculated column, I would first make sure you are looking for its "Real" name. If the column has been renamed at any point, it will still retain its original name.
Go into your SharePoint list settings and click on the calculated column to edit it. Then look in the URL in the browser. The URL will end with field=something. something is the REAL name of the column.
That is what you will be looking for in the Edit Fields of the DataTable.
I hope this is helpful for you.