How to create sfcalender event from sqflite database in flutter

Question

I am going to create a flutter event app using sfcalender and sqflite. My problem is how can I show sfcalender event from saved event in database? This is my table:

await db.execute('''
      CREATE TABLE leave_Calender_Details(
          "leaveType" TEXT,
          "start_Date" TEXT,
          "end_Date" TEXT      
      )
      ''');

Here is my my helper class:

Future<List<LeaveCalenderLeaveDetails>> getAllRecordsforCelandar() async {
    Database db = await instance.database;
     var _leaveCalenderDetails = await db.query('leave_Calender_Details',
        columns: ['leaveType','start_Date','end_Date']);
     List<LeaveCalenderLeaveDetails> _leaveDetailsList = _leaveCalenderDetails.isNotEmpty
        ? _leaveCalenderDetails.map((c) => LeaveCalenderLeaveDetails.fromMap(c)).toList()
        : [];  
    print(_leaveDetailsList) ;
    return _leaveDetailsList;
  }

Here is my model class:

class LeaveCalenderLeaveDetails {
  String leaveType;
  DateTime start_Date;
  DateTime end_Date;

  LeaveCalenderLeaveDetails(
      {
      required this.leaveType,
      required this.start_Date,
      required this.end_Date});

  factory LeaveCalenderLeaveDetails.fromMap(Map<String, dynamic> json) =>
      LeaveCalenderLeaveDetails(
        leaveType: json['leaveType'],
        start_Date: json['start_Date'],
        end_Date: json['end_Date'],
      );

  Map<String, dynamic> toMap() {
    return {
      'leaveType': leaveType,
      'start_Date': start_Date,
      'end_Date': end_Date,
    };
  }
}

How can I add event into sfcalender?