Here is one way of doing it:
using System.Text.RegularExpressions;
string text = "The quick brown, and lazy, fox jumped over the tall-green fence!\r\n What a sight it was. ";
int WordCount = Regex.Matches(text, @"\b[A-Za-z0-9]+\b").Count;
int ParagraphCount = Regex.Matches(text, @"[^\r\n]*[^ \r\n]+[^\r\n]*((\r|\n|\r\n)[^\r\n]*[^ \r\n]+[^\r\n]*)*").Count + 1;
Console.WriteLine(text);
Console.WriteLine($"contains {WordCount} words and {ParagraphCount} paragraphs.");
Outputs:
The quick brown, and lazy, fox jumped over the tall-green fence!
What a sight it was.
contains 17 words and 2 paragraphs.