openwrt, default network config

Question

Computer networks

Good time.
There is an idea to put openwrt on the router without a web muzzle. Now I'm trying to find out as much as possible about the initial setup, because. I do not want to be left without an Internet with an unconfigured router.
In principle, everything is written in the wiki quite intelligibly, but I did not understand such a thing.
1. Does the DHCP server work immediately after flashing?
2. Does the question of information exchange between computers in LAN ports, as well as with computers via WiFi, need additional gestures?

Answer 1

Thank you. And after turning on Wi-Fi, will there be packets between devices from wired and wireless networks?