1. Open your .FLA file from ‘sources/flash’ folder in Adobe Flash program.
2. We should add a new symbol (Insert ->New Symbol or CTRL+F8)
3. Change the symbol type to ‘Movie Clip’ and give it a name.
4. Import your .FLV file to the library (File -> Import to library).
NOTE: you should place video file into the newly created Symbol (my_video movie clip).
5. Browse for your video file and click Import button.
6. Follow the process to import the video file:
7. Now, you have your Video file in the ‘my_video’ movie clip.
8. Open the flash library (CTRL+L) and locate your pages movie clip. Open the movie clip in the Scene by double clicking on the object.
9. Navigate to the page, on which you wish to place your video.
10. Drag the ‘my_video’ movie clip from the Flash Library right into the Scene. Place it on your page where you want.
11. Publish your .FLA file to see the preview.
Feel free to check the detailed video tutorial below:How to embed video in Flash template (AS 2.0),