Hi

I guess you are working in Storyboard mode.  It is easier if you are in Timeline mode.

1.  Drag the clips to the right of where you want to insert the text ( as a Title) to the right to create a gap - we can adjust the actual length of the title later.

2.  Position the timeline cursor at the point in the gap where you want the title to be and press the T key to insert a title object on to the timeline entering the text and other settings you require.

3.  Close up any gaps by making the transition from previous object to title and title to following object as cuts. 

4.  Adjust the length of the title and set any transition you require if anything other than a Cut.

HTH

John