I want to connect my Pi 1b to my router with a Lan cable and turn it into an access point. That I would like to be able to connect to the Raspberry Pi with my laptop and to be able to receive WLAN. Is that okay, or do I need an adapter or something similar for the Raspberry?
There are millions of guides: Google Rpi Access Point.
https://www.raspberrypi.org/documentation/configuration/wireless/access-point.md
You need a WLAN adapter because in a Raspberry Pi no one is installed.
Quite simply, you have to go to the GPIO24 pin: here the pinout plan http://www.raspberry-pi-geek.com/howto/GPIO-Pinout-Rasp-Pi-1-Rev1-and-Rev2
But you will catch the signal raw, that is, binary, i. You need a lot of software to do that. Then just bring the signal out on another pin.
