Yes, it's a one-game win, and Chelsea played exceptionally well in that match. Perhaps they'll face Paris Saint-Germain again in the Champions League and not play the same way. Perhaps they'll play the same way and beat Paris Saint-Germain again—time will tell. Chelsea drew their first Premier League match, but because every match is important in the Champions League, they should strive for more wins.
The results of any match in any competition will not affect the outcome of the Champions League.
If Chelsea and PSG meet again in the Champions League, both clubs will undoubtedly improve their performance, and their performances will be different from those they perform in other competitions.
The Champions League is one of the biggest competitions every club will pursue.
However, I doubt these two clubs will meet again in the Champions League, as I predict they will likely be eliminated by stronger clubs before they meet.