Yes, but don't forget you will have to clear immigration upon departing as well, so do leave enough time to get back through security and immigration after you have met your friend (the cut off time is 1 hour before departure and they can be very strict). You won't technically need to check-in again, as you should already be checked through and issued with a boarding pass to CDG at your origin point. If not, you can of course easily get another BP at a desk.