I managed to get this to work.
So i plug the Samsung phone to "UGREEN USB C to Ethernet Adapter”. I Plug the ethernet to WAN.
Samsung phone default tries to connect and fails. When you select connect it keeps failing to connect.
There are 2 ways to get to “ETHERNET” setting and they do 2 things in samsung android 11+ phones.
1.Settings → Connections–> More Connection Setting–>ETHERNET
2. Settings → Connections → Mobile hotspot and tethering → Ethernet Tethering
When I use number 2 .“Mobile hotspot and tethering” and connect ON it works i get a cable connection to FLINT so IP gets assigned (DHCP).
Credit to this youtuber