Sometimes I feel like I lack a fulfilling life.

I stay at home every day, browsing the computer, reading the news, scrolling through social media, but in reality, it's like looking at flowers through fog, trying to catch the moon in the water—there's no solid, genuine engagement.
I really want to go to a bar and take a look, see how they party late into the night, watch them dance and sway, but I am socially anxious.
I'm afraid that in that environment, I will feel very awkward.
What if a girl flirts with me? I might get nervous and be at a loss for what to do.
Has anyone been there? Please share the specific experience.