how to read word file into richtextbox using asp.net in c#

Microsoft.Office.Interop.Word.ApplicationClass Application =  new Microsoft.Office.Interop.Word.ApplicationClass();
            object nullobj = System.Reflection.Missing.Value;
            object file = Server.MapPath("CV.docx");
            object value = System.Reflection.Missing.Value;
            Microsoft.Office.Interop.Word.Document doc = Application.Documents.Open(ref file,ref nullobj, ref nullobj, ref nullobj,ref nullobj, ref nullobj, ref nullobj, ref nullobj, ref nullobj,ref value,ref value,ref nullobj, ref nullobj, ref nullobj, ref nullobj, ref nullobj);
 
            doc.Activate();
            //var ss = doc.Words[0];  
            var x = doc.Words;
            cn.Open();
            SqlCommand cmd = new SqlCommand("SELECT DISTINCT SkillId FROM tblSkills ORDER BY SkillId", cn);
            cmd.CommandType = CommandType.Text;
            SqlDataAdapter da = new SqlDataAdapter(cmd);
            DataSet ds = new DataSet();
            da.Fill(ds);
            string SkillName = "";
            string SetSkills = "";
            string FetchSkill = "";
            
            if (ds.Tables[0].Rows.Count > 0)
            {
                string Doc_Content = doc.Content.Text;
                for (int i = 0; i <= ds.Tables[0].Rows.Count - 1; i++)
                {
                    SkillName = ds.Tables[0].Rows[i]["SkillId"].ToString();                    
                    if (Doc_Content.ToString().IndexOf(SkillName) > 0)
                    {
                        SetSkills += SkillName + ",";
                    }
                    
                }
            }
 
            cn.Close();
            
            txtResult.Text = SetSkills.TrimEnd(',').ToString();
            // txtContent.Text = Doc_Content;
            doc.Close(ref nullobj, ref nullobj, ref nullobj);