I want to bring my spouse and 2 kids for 4 month in China

Hi Sir,
I am already in China and having work permit and residence permit as I am emplyee of a Chinese company.
How I can bring my spouse and 2 kids here in China ?
Further my family will come here in China on F visa or Z visa and police report is required for my spouse or not ?
Is it acceptable if marriage certificate is attested by Lahore foreign affair office or I need to attest it from Islamabad foreign office ?

Br,
Kashif