Use this piece of code :
That would add the image and then a line to it.
object StartPos = 0;
object Endpos = 1;
Microsoft.Office.Interop.Word.Range rng = doc.Range(ref StartPos, ref Endpos);
object NewEndPos = rng.StoryLength - 1;
rng = doc.Range(ref NewEndPos, ref NewEndPos);
rng.Select();
var pText = doc.Paragraphs.Add();
pText.Format.SpaceAfter = 10f;
pText.Range.Text = String.Format("This is line");
pText.Range.InsertParagraphAfter();
object StartPos1 = 0;
object Endpos1 = 1;
Microsoft.Office.Interop.Word.Range rng1 = doc.Range(ref StartPos1, ref Endpos1);
object NewEndPos1 = rng.StoryLength - 1;
rng1 = doc.Range(ref NewEndPos, ref NewEndPos);
rng1.Select();
doc.InlineShapes.AddPicture(loc +@"\" + dt + ".jpeg");
I hope this would help.