You could have found the answer by searching the forums but in short you need to configure as follows:
Telephone Line from Outside/DP->Splitter->DSL/Modem->TP-Link's ADSL Port (i.e., remove any old modem/router from PTCL)
- PPPoE with LLC Encapsulation
- VPI/VCI 0/103 for Copper
- VPI/VCI 8/81 for Fiber
- Correct username and password for DSL
You may also ask for settings from helpline or use same settings as used by PTCL in their configuration videos! Use the Manual for the TP-Link!