content of /etc/network/interfaces

auto lo
iface lo inet loopback
iface eth0 inet dhcp
allow-hotplug wlan0
auto wlan0
iface wlan0 inet dhcp
wpa-conf /etc/wpa_supplicant/wpa_supplicant.conf

and /etc/wpa_supplicant/wpa_supplicant.conf

country=PL
ctrl_interface=DIR=/var/run/wpa_supplicant GROUP=netdev
update_config=1
network={
ssid=”MY AWESOME NETWORK”
psk=”MY PASSWORD”
}