I have code to generate SHA512 from string.
 public static string GetCrypt(string text)
        {
            string hash = "";
            SHA512 alg = SHA512.Create();
            byte[] result = alg.ComputeHash(Encoding.UTF8.GetBytes(text));
            hash = Encoding.UTF8.GetString(result);
            return hash;
        }
     
     
     
    