Hi  @Stepanmanak,

According to the translation of Google Translate, I think that your question is to configure the RE330 network through Ethernet cable or distribute the RE330 network to the back-end device through the LAN connector through Ethernet cable. If there is any discrepancy, please describe it in English.

If you want to configure the RE330 via Ethernet cable,that is, the RE330 will access internet from the router via wired connection. Then you can set it in Access Point mode:

For Tether App: https://www.tp-link.com/support/faq/2852/

For Web Management Interface: https://www.tp-link.com/support/faq/1401/

If you want to distribute the RE330 network to the back-end device through the LAN connector through Ethernet cable, yes, you can directly use ethernet cables to connect RE330, LAN connector and client.

Thank you.