If you are this early career and the company is still paying you, PIP or no PIP, it's very likely that they want you to succeed. Question your assumptions and make sure you really understand the feedback they are giving you. Don't put in extraordinary hours (you want to have clear judgement, get plenty of sleep) but look for every resource, mentors, books, ask for help, and focus on doing your best. This will put you in the best possible light no matter what happens.

There are a lot of different companies out there each with a different culture. One of them might be a better fit.