I am not able to use Any() on XmlNodeList. I have also used System.Linq and System.Xml.Linq namespaces as well. But still I'm not finding any such extension methods on XmlNodeList.
How I can use it??

The problem is that XmlNodeList only implements IEnumerable, not IEnumerable<T>. The simplest way to use LINQ on it is to call Cast:
var query = nodeList.Cast<XmlNode>()
.Where(...)
...;
Alternatively, ditch the old XML API and use LINQ to XML, which is a much nicer API in general and supports LINQ really nicely :)
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