Advice for first upcoming legal job

Howdy again, incompetent 3rd year law student here back with more eye-roll worthy questions. I've recently managed to - by what I can only assume was a hilarious mistake - land a position as a paralegal / doing work experience at a small local firm. It deals with commercial, regulatory, family and import & export law.

I have dabbled with a CLC before and briefly shadowed a barrister (read: capitalised on a couple months worth of free lunches) in my first year. Unfortunately, that's about as far as my experience goes. This will be my first time in an actual office doing actual... things.

I'm at a bit of a loss, hopefully understandably, in that I'm not entirely sure what to expect. Are there any documents/processes in particular I should brush up on before I start (next week)? Etiquette and such I should follow? Who I should go to for help? Any tidbits of advice in general?

Sincerest thanks in advance for any and all words of wisdom.