Unfortunately, you're also entering into big tech at a time when most big tech companies are laying people off. It's going to be a highly competitive time.

Personally, I'd follow the process, put my nose to the grindstone, and work hard to improve. It's about all you can do, since you're playing in their sandbox. Don't take your paycheck for granted, put money away for a rainy day.

If anything does happen (and I'm not going to sugar coat it, the PIP is definitely the first step out the door), remember that not everyone is a fit for every job, but it doesn't mean you're not going to be able to do tech work. It might just mean you need to find a less competitive job outside of the highly competitive big tech field.

My first job wasn't a good fit for me. I'm a doer, and that job was about planning things that might never get done ever. I'd just put a plan together and they'd tell me to put it on the shelf and start on the next one. Spent a lot more time on reddit than I'd like to admit, I found it hard to get motivated. My next job was much more immediate, things I did would be rolled out immediately once testing was successful. I found that it was a much better fit for me, and I did very well in that job.