You have to use the TPlink first since it houses your modem. You can turn everything off so it acts as nothing more then a modem plugged into your NETGEAR router.
If you asking about setting it up as a wireless repeater then that's another issue. Short answer is no. Again you must use the TPlink first as a modem and or router. Some routers have a repeater mode. The low end NETGEAR routers generally so not. It can be configured as an access point but that requires a wired connection to your TPlink. Ifd you really want or need a repeater you will probably need to buy one. If so look at the NETGEAR rpt2000. A solid basic 2.4 ghz repeater.
Bob Silver
NETGEAR Networking Consultant