CSV is not a "formatted" file: it is literally a text file containing data that is separated by commas, with rows delimited by lines:
1, Hello there, 3
2, Goodbye, 4
Is two rows, each of three columns.
To allow commas and newlines to be embedded in a column, you can use double quotes to surround text:
1, Hello there, 3
2, "Goodbye, 4"
3, "Hello
there", 5
Is three rows, 3 columns, on row 1, 2 on row 2, and 3 on row 3.
That's it for CSV formatting - no CELL, no references, no "this is a string" setting.
If you want more complicated formatting - heck if you want any formatting - then CSV is the wrong choice of file format: you need a DB, or JSON, or XML, or XLSX.