After Click on Add reference then following window will be appear and select Microsoft Word 12.0 Object Library dll and click ok.

Step 3: After the Successfully added dll in your project write the following code to create MS-Word Document.

Here I am making a window form which perform two task first one is create ms-word document and second one is read document. 

Step 4: Now debug the code and click on the create button after clicking create button the create button click event generate

public partial class Form1 : Form
    {
         // create MS-Word application  
         Microsoft.Office.Interop.Word.ApplicationmsWord=new Microsoft.Office.Interop.Word.Application();
         // create Word document reference
         Microsoft.Office.Interop.Word.Documentdoc;
         // Create misssing value object 
         objectobjMiss=System.Reflection.Missing.Value;
         // Create end of document object
         objectendofdoc="\\endofdoc";
         publicForm1()
         {
            InitializeComponent();
         }
         /// <summary>
         ///This Method create first paragraph  
         /// </summary>
         public voidFirstPara()
         {
             // create first paragraph with reference name
            Microsoft.Office.Interop.Word.Paragraphpara1;
             // add paragraph with document 
            para1=doc.Content.Paragraphs.Add(refobjMiss);
             // create object of heading style 
             object styleHeading1="Heading 1";
             //add heading style with paragraph
            para1.Range.set_Style(refstyleHeading1);
             // Write text of paragraph 
            para1.Range.Text= "Hello Arun, How are You?";
             //set font style of paragraph 
            para1.Range.Font.Bold=1;
             // set space after write format of paragraph 
            para1.Format.SpaceAfter=24;
             // selection range of after insert paragraph 
            para1.Range.InsertParagraphAfter();
         }
         /// <summary>
         ///This Method Create Second Paragraph
         /// </summary>
         public voidSecondPara()
         {
             // create second paragaraph  with paragraph reference name para2
            Microsoft.Office.Interop.Word.Paragraphpara2;
  
             // add second paragraph with documnet
            para2=doc.Content.Paragraphs.Add(refobjMiss);
             // set paragraph heading style 
             object styleHeading2="Heading 2";
             // add heading style with paragraph
            para2.Range.set_Style(refstyleHeading2);
             // second paragraph text  
            para2.Range.Text= "Hii This is Arun I am fine and you?";
             // set second paragraph font style 
            para2.Range.Font.Bold=1;
             // space or font size style like 24pt, 25pt etc.
            para2.Format.SpaceAfter=24;
             // set selection range of paragraph 
            para2.Range.InsertParagraphAfter();
         }
         /// <summary>
         ///This Method create table in ms-word document
         /// </summary>
         public voidCreateTable(intRow,  intcolumn)
         {
  
             // create table in word documnet in word application with table reference name tbl1
            Microsoft.Office.Interop.Word.Tabletbl1;
             // calculate the range of endofdocu
            Microsoft.Office.Interop.Word.RangewordRange=doc.Bookmarks.get_Item(refendofdoc).Range;
             // add table with document with number of row and column
            tbl1=doc.Content.Tables.Add(wordRange, 3, 3, refobjMiss, refobjMiss);
             // set border visibility true by input 1 and false by input 0
            tbl1.Borders.Enable=1;
             // set text in each cell of table 
             for (intr=1; r<=3; r++)
            {
                 for (int c=1; c<=3; c++)
                {
                    tbl1.Cell(r, c).Range.Text="r"+r+"c"+c;
                }
            }
         }
  
/// <summary>
///This method creates ms-word document and adding some paragraph, table and much more.
/// </summary>
  
         public voidCreateMsWord()
         {
             try
            {
                // show ms-word application
                 msWord.Visible=true;
                 // add blank documnet in word application
                doc =msWord.Documents.Add(ref objMiss, refobjMiss,  refobjMiss,  refobjMiss);
                 // create first para 
                FirstPara();
                 // create Second para
                SecondPara();
                 // create table
                CreateTable(3, 3);
  
            }
             catch (Exception ex) { MessageBox.Show(ex.ToString()); }
           
         }
  
         /// <summary>
         ///create button click event  
         /// </summary>
         private void btn_Create_Click(objectsender, EventArgse)
         {
             // call the method to create ms word document file
            CreateMsWord();
         }

Desired Output:

When you click on Create button then following ms-word document file created.