Italy->Hong Kong & stopover in Beijing Capital Airport

Dear office,

I’ll travel to hgk from Italy and I’m stopping in PEK for two hours.
Italy-pek and pek-hgk are served by the same company, AirChina.
Terminal 3 will be the one where i’ll land in pek and from which i’ll Leave for hgk.
Please, would you help to solve my following doubts?

1. Since i’m Staying in the airport in the same terminal and i’m Not going to leave it during my stopover time, do I need any kind of visa?
2. Is usually the company taking care of the checked luggage between the two flights (the ticket is the same) or do I have to pick them up once again and pass through new procedures?
3. Are two hours enough for going to a gate to the other within the same terminal (n.3), having taken into account new possible controls?

While looking forward to having your answers I deeply thank you in advance