A family of Microsoft relational database management systems designed for ease of use.
"Calculated Fields" in Tables are not (by any means!) the only calculations you can do in Access; they were introduced just a couple of versions ago to accommodate Sharepoint, which has now pretty much been abandoned. I would not recommend using them unless you have a very specific need to do so.
Instead, base Queries on your tables, and use expressions in those Tables.Queries.
That said, the Format() function can be useful, but maybe less than you think; it converts a Number or Date value to a Text string. If you just want to format a value for display, base a Form or Report on your table (or more likely on a selective Query of your table), and set the Format property of a textbox on that object.
Edited 9:51pm 2/3 to correct Tables to Queries