There are various ways to read xml data.
you can directly read xml file using data set ,that can be achieved as
string path = "D:\XmlData\data.xml";
DataSet ds = new DataSet();
ds.ReadXml(path);
Then you can processed data in dataSet 'ds' as of your requirement.
To read node by node (record by record )
string path = "D:\XmlData\data.xml";
XmlDocument xmlDoc = new XmlDocument();
xmlDoc.Load(path);
XmlNode Node = xmlDoc.SelectSingleNode("root/common");
foreach(XmlNode SingleNode in Node.ChildNodes) {
}