This is an implementation of the NAT Router as documented here:
You can configure the NAT Router either by using the Web Config Interface or Command Line Interface (serial console):
Web Config Interface
The web interface allows for the configuration of all parameters. Connect you PC or smartphone to the WiFi SSID "ESP32_NAT_Router" and point your browser to "http://192.168.4.1".
Command Line Interface
For configuration you have to use a serial console (Putty or GtkTerm with 115200 bps). Use the "set_sta" and the "set_ap" command to configure the WiFi settings. Changes are stored persistently in NVS and are applied after next restart. Use "show" to display the current config.