To retrieve a list of child nodes by one of their properties which matches a string value, you could use something like the following:

@{
    var stringValue = "YourStringValue"; 

    var childNodes = Model.Content.Children.Where(x => x.GetPropertyValue<string>("yourProperty") == stringValue);

    if (childNodes != null)
    {
        // Iterate through childNodes
        foreach (var item in childNodes)
        {
            // Apply your logic here
        }
    }
}