Who are you when you aren’t acting the way your friends expect you to? Free from that possibly subconscious pressure what do you do? You can’t exist in a vacuum because we are human beings and socially conditioned (not always a bad thing!) but you can get close when you change up your situation. Observe yourself closely.. where is the divergence between what you think of yourself and what you actually do? Would you have done the same thing in front of your friends? Your parents? Personally I am wildly different with my family, friends, and alone. I like the solo version of myself the best, so I try to spend as much time with him as possible.
This isn’t to say that who you are with others isn’t who you are, that’s an important part of you too!! But if you’re looking to understand yourself as an individual then you need to understand as many aspects as you can. Most people do not do activities alone so I think it is a great place to start.