Bridge mode
Bridge mode allows your OpenWrt device connects to the LAN network as a bridged AP.
You can use this device to extend your current router or even just plays the role of a gateway which handles all the traffic flows through your local network. More details can be found in this OpenWrt official page: https://openwrt.org/docs/guide-user/network/wifi/bridgedap
Router mode
The router mode will be easier to understand. It’s more of a new router device added into the current local network. This router has it’s own LAN and WAN interface. And it’s LAN interface works on a different layer which controls by the NAT rules.
You can also go to the OpenWrt official page to see how it works: https://openwrt.org/docs/guide-user/network/routedclient
Compile your own packages
In case of there are some packages are not compatible with your kernel or it doesn’t exist in your package list. You have to compile them from the source by yourself.
clone the whole project and follow the compile tutorial to config properly. You can edit your configuration conveniently through menuconfig. Assume that I need to build the drivers for my network adapter, I should choose the compatible driver in the list.
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