I have made my Raspberry Pi an access point and DHCP server and it is working fine. I have used
iface wlan0 inet static and provide static ip address for it and I have left
iface eth0 inet manual as it is.
The part I am confused about is do I need to configure eth0 with a static IP address in order to make the Raspberry Pi act as a router, or is just configuring wlan0 enough? In what case do we need to configure interface wlan0 (wireless) and eth0 (wired)? What commands do we need to add to make the Raspberry Pi a router as I have already made it an access point?