Anything I should know?
This is the basic difference between Catholics and "high church" Protestants. Both are Christian and catholic (in the universal sense).
If someone is from the PNCC can they work in a Roman Catholic church?
It depends on what you mean by this. PNCC members are not considered Roman Catholics by either themselves or the Roman Catholic Church. As such, PNCC clergy are not eligible to serve in the Roman Catholic Church. Unconfirmed Roman Catholics (including most PNCC members) can not receive communion in the Roman Catholic Church. Without a dispensation, Roman Catholics may not marry PNCC members and remain in good standing as Roman Catholics.