Please let me know the best option to go from pudong airport to the train station.

You are suggested to take bullet train to Changzhou from SH Main Railway Station.
Upon arrival, take subway line 2 from PVG to People's Square and transfer to line 1 to Main Railway Station. It takes around 75 mins. And the ticket fare is CNY 7 per person.
After arriving, the train schedules after 16:30 are from 16:49 to 21:43. The duration is about an hour. The ticket fare of second class seat is CNY74.5, first class seat is CNY119.5 and VIP seat is CNY143.5.