Best advice ive had.. "fake it till you make it "

Don't. Please don't.
For the job interview that might be fine. But please, when you come to a new team and you really don't have much experience, then just don't.
It will harm your team and in the long run it will harm you. Especially if you take it so hard that you won't take any advice.
We have that situation at work right now. Guy fresh from university thinks he knows all is writing horrible code, with a horrible structure and he has a horrible attitude.
But he listens to no one.
Even worse: most of the time he just tells you he understood, but does something else, so he says this just that you leave him alone.

Honestly, there is no shame in acknowledging (to yourself and your colleagues) that you don't know all. That is valid for everyone, people just starting out and also senior developer. Especially in our field, it is rather healthy to expect to learn something new instead of acting like one already knows everything.