@Bruno1987 

Hi, thanks for posting question here.

There are multiple methods to retrieve your Wi-Fi password:

1. The Router's label

    If you did not customize your Wi-Fi password, the default SSID and password are printed on the label, the label is at the back of the Router.

2. Web Management Interface

    Connect your PC to the Router by Ethernet, login http://tplinkwifi.net with the router admin password, go to Advanced > Wireless > Wireless Settings to view your Wi-Fi password.

3. Tether APP

    Open the Tether APP and login your device with the admin password, go to Tools > Wireless Settings to view your Wi-Fi password.

For detailed pictures, please refer to this FAQ.