IMO piaware is not a best choice. Better try adsb-receiver project image from Joe Prochazka. Automated setup of dump1090, feeders, local stats on Pi and many extras. RB feeder has to be added manually. WiFi setup on any Pi is easy. Just create file wpa_supplicant.conf on boot partition of SD card, open in text editor and paste following:
country=xx
ctrl_interface=DIR=/var/run/wpa_supplicant GROUP=netdev
update_config=1
network={
ssid="networkname"
scan_ssid=1
psk="netpassword"
key_mgmt=WPA-PSK
}
Change xx to your country code (fe. US for USA),networkname and netpassword to yours, save.
Insert card into Pi and power on. WiFi will work.