Hi I am making a fps and I was wondering how to you make a video to go in the start of a game... Like in that boot camp game on unity.com and you wer in a helecopter and then you repaled down
You have two options: pre-rendered movies and in-game cut scenes.
A movie is a prerendered video that gets played back. It doesn't even have to match the style of the rest of the game- it can use actors, computer graphics that take hours to render, etc. In other words, it's not an in-engine scene.
But there is another way, and that is to animate objects and the camera within the Unity engine. Instead of the player controlling the action, the code is.
The helicopter scene you refer to looks like it is generated by Unity on-the-fly, an in-game cut scene. Now it's possible to use Unity to pre-render a scene to turn it into a movie, which can make it hard to tell the difference. But if you move the mouse while the helicopter is in view you'll see that the camera moves too. So this is almost certainly "just" another Unity scene, not a prerendered movie.
The idea is simple: if you know how to move objects using a script, then you already know enough to do a simple cut-scene with action and a moving camera. The more complicated the scene, the fancier you'll need to get. You may end up using Unity's animation features, learning ways to control the camera, "tweening", and other topics.
The Lerpz tutorial includes two simple cut-scenes, as I recall. One was when you unlocked your ship; it shows you what's happening on the other side of the map. And I think there was a game-win animation as well. So you could read those parts of the tutorial to get some ideas.
You might want to look at Movie Textures but you'll need Unity Pro.
As for doing it at the start, you create a scene with just the movie as the first scene in your game, which then loads your main game scene once the movie is finished.