Flutter: How can I update a CSV cell?

I am creating a language app and the class material is stored in a CSV. So far I can read a specific cell from the CSV but I don't know how to update a specific cell and I can't find anything online on how to accomplish that. How can I code that?

I am using the csv package from pub.dev. This is how I am reading from the csv:

  readCSV(row, col) async {
    var csvFILE = await rootBundle.loadString("assets/class01.csv");
    List<List<dynamic>> csvDATA = CsvToListConverter().convert(csvFILE);
    
    setState(() {
      displayText = csvDATA[row][col];
    });
  }