Configs are device specific, as they are closely related to the hardware. Your TP-link config has probably locked the network stack pretty fully.
You might try Entering the OpenWrt failsafe mode, and then resetting the router with firstboot. (But that might be difficult due to the invalid config. Failsafe should still work, but it is not quite foolproof)
https://openwrt.org/docs/guide-user/troubleshooting/failsafe_and_factory_reset
With R7800, the more sure thing to fix things, might be to enter the R7800 TFTP recovery flash mode, and then flash a new R7800 firmware image (a factory image, not sysupgrade).
- https://openwrt.org/toh/netgear/r7800#debricking
- Netgear R7800 exploration (IPQ8065, QCA9984) - #5 by hnyman
(The TFTP recovery is built into the Netgear OEM bootloader, so OpenWrt firmware or settings have no impact on that)