Calc basics: formatting or styles?

Three decades and much software and languages later, I am finally forced to learn spreadsheets.
However, my intuitive sense that designing a spreadsheet around the necessary columns and their respective data types seems to be missing from the many resources I have started with over many hours.

I need to design a bookkeeping spreadsheet/template for expenses, to start with.

It seems to me that I first need to set the titles for the columns in row A, and then somehow set the specific data types for the columns, such as “date,” and “$(amount)”.

Is the “Format Cells” dialog the best/correct way to begin to design a sheet/template?

Or is there some other approach using styles?

Also, if another question is appropriate, are there some online resources for LO Calc templates?