I know but I don't. Am I that bad?

So, I graduated this year and joined a startup as a frontend developer 6 months back. Previously I had around 9 months of internship experience in 2 startups. When I was doing my 1st internship, it feels like I know everything about frontend development, I really struggled in my 2nd internship as I am somewhat bad in coding part, struggled but at the end of internship, learnt a lot, got job on that skill, not a great CTC but not too bad. Recently, I started interviewing and seeing many posts on twitter, learnt many concepts, a simple http request has so much thing that sometime it goes out of brain, all started with an SDE-2 frontend interview at Plum, where I didn't know anything. I wanted to go for backend but I am not able to even cover whole frontend part. I don't know if it is normal or not but I feel software engineering is not my cup of tea even though I am handling all the frontend stuff at my company and thinking to switch into product side of things(product management). Seeking some advice what should I do?