code.gs

function writeDataToFirebase() {
    var firebaseUrl = "https://makerqr.firebaseio.com replace this with your own";
    var secret = "the firebase database secret here";
    var base = FirebaseApp.getDatabaseByUrl(firebaseUrl, secret);
    var mySheet = SpreadsheetApp.openById("the id of your spreadsheet");
    var dataSheet = mySheet.getSheets()[1];
    var lastRow = mySheet.getLastRow();
    var lastColumn = mySheet.getLastColumn();
    var data = mySheet.getSheetValues(1, 1, lastRow, lastColumn);
    var dataToImport = {};
    for (var i = 1; i < data.length; i++) {
        dataToImport[i] = {
            name: data[i][1],
            email: data[i][2],
            gender: data[i][3],
            age: data[i][4]
        };
    }
    base.setData("maker", dataToImport);
}
function addNewData() {
    writeDataToFirebase();
}