@Skyline_UK

First, make sure you are in Timeline view. (From your description I think you are but just need to be sure!)

Place the "background" clip on track 1. (If you have audio on the clip and have selected to have audio and video on separate tracks the audio will default to track 2.)

Place the clip of the man on the next higher-numbered track, i.e., either 2 or 3, depending on whether you have the audio of the background on a separate track, as above.

Look at the video object which is the track of the man speaking. Find the marker/triangle highlighted in my screenshot below. (For this demo I have used an object on track 1, yours will be on either 2 or 3, as I wrote earlier.)

Place your cursor on the triangle, hold down the left mouse button and carefully drag it downwards. As you do the image of the man will increase its transparency (or decrease its opacity) and the image of the galleon will gradually "emerge" behind him.

However, this will make the image of the man appear somewhat "washed out" (the further down you drag that triangle, the more washed out he will be) and may not achieve exactly what you want.

To achieve full visibility of the man against the background of the galleon you will need to explore the use of Chromakey, where the man is filmed against a background of a single solid colour, most commonly Green but can also be Blue. The chromakey effect then "removes" that single colour, leaving the man standing against a fully-transparent background, through which you see the galleon.

HTH

Jeff
Forum Moderator