Check the sticky post " WA3002G4 Quick reference " (Similar UI).
Go to the WAN page of modem, click " edit" for the VPI/VCI 0_35 entry. In the very next page, you will find an option to select bridge mode instead of PPPoE. Change it, thats all.
To be safe, take a back up of your modem settings and save it in your PC before trying things on modem menu.