Assuming your Matinee is all set up and ready to go, you can add this string to the level blueprint.
When you record a movie through the matinee editor, it will run through your sequence, and then it will place you, as the player, in the spawn location that you have set up. You can then play as you normally would, walk around, and when you’re finished, end the recording.
You just need to make sure the container containing the spawn location is facing the correct direction and is in an accessible place. That’s about it through, pretty simple. 