Replace a paragraph in the <title> tags with c#

Question

I am creating a function that can replace a paragraph in the tags and delete the scripts with tags, can you see the syntax I have written correctly?
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StreamReader tx = new StreamReader("page2.txt");
string title = Regex.Match("page2.txt", @"\<title\b[^>]*\>\s*(?<Title>[\s\S]*?)\</title\>", RegexOptions.IgnoreCase).Groups["Title"].Value;
List<string> lines = new List<string>();
while (!tx.EndOfStream)
lines.Add(tx.ReadLine());
string linetoreplace = lines[0];
string contents = tx.ReadToEnd();
StreamWriter sw = new StreamWriter(" how to ? thay the");

}
public static void DelJs()
{
StreamReader tx = new StreamReader("page2.txt");
Regex rRemScript = new Regex(@"<script[^>]*>[\s\S]*?</script>");
newtx = rRemScript.Replace(oldtx, "");
return newtx;
}

Answer 1

someone ?

Answer 2

...

Answer 3

???

Answer 4

????

Answer 5

nobody else ?