Barcelona is not invincible, Chelsea beat PSG in the Club World Cup, and Barcelona didn't even reach the UCL final, so there's no need to be upset because they drew Barcelona, I hate that they drew Barcelona, it shows what they're made of, Barcelona is a great team, but if Chelsea is good they have to play against the good ones, and if they're good they should get through without any problems, in football you can't and shouldn't ever be afraid.
This isn't about fear, but about how the team handles the immense pressure of facing a much tougher opponent. I agree that if Chelsea want to advance in the Champions League, they have to be able to face any team, but this has happened too quickly, as they have to face a tough opponent in the group stage. Regardless, there's still hope, and it all depends on how Chelsea can get through the few matches and accumulate points in the group stage. Even strong teams sometimes struggle to achieve good results, and Chelsea just needs to perform consistently to prove it.