Papers in UK

Have you looked at all on the www.gov.uk website? Lots of info there to start with.

To come here all you need is your Italian passport.
To start work you don't need anything else, but you need to have a valid National Insurance number within 3 months of starting. You can apply for it online but you will be called to an interview at a JobCentre in order to get it. You need to apply soon after you start work, they ask for all sorts of papers (from your employer, proof of address - bills, bank statements, and so on) and you are likely to not have all of them the first time you go for the interview.
It's difficult to get a bank account if you don't have bills in your name at your UK address, and often you can't get utilities in your name if you don't have a bank account. Bit of a tricky situation for many people. If you get caught in this, try Santander, they are the most flexible bank in this regard.
If you plan to work self-employed, you need to apply online to register as self-employed, and you need to get a NI number afterwards (again, within 3 months).
If you are renting your own apartment or house, you need to register with the local council for council tax (it's done for you if you rent from a letting agency, but if you rent privately you can't rely on the landlord to do it).
And that's about it.