This instruction should work for other Pi with built-in WiFi.

Step 1: Change default DNS

Edit /etc/systemd/resolved.conf

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# Use Google DNS as default DNS
DNS=8.8.8.8
# Fallback to local DNS
FallbackDNS=192.168.1.1

Step 2: Connect to Wi-Fi temporarily

Generate a WPA PSK from an ASCII passphrase for your WiFi

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sudo wpa_passphrase [SSID] [passphrase] | sudo tee /etc/wpa_supplicant/wpa_supplicant.conf

# example
sudo wpa_passphrase "Xing's WiFi" pass1234 | sudo tee /etc/wpa_supplicant/wpa_supplicant.conf

You should see the file /etc/wpa_supplicant/wpa_supplicant.conf generated with content like following. It is highly recommended to delete the plain text password in the comment.

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network={
    ssid="Xing's WiFi"
    #psk="pass1234"
    psk=e851df315f1663055025c04c796ca377bc96240bf0bb82e417ce47051490bf8c
}

Start WPA supplicant (Raspberry Pi’s built-in WiFi should have network interface name wlan0, if not, change following accordingly)

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sudo wpa_supplicant -B -i wlan0 -c /etc/wpa_supplicant/wpa_supplicant.conf

Obtain IP through DHCP (assuming DHCP is enabled on your router)

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sudo dhclient -r
sudo dhclient wlan0

Now if you use ifconfig you should see internal IP allocated to wlan0 and you should be able to access internet.

Step 3: Connect to Wi-Fi persistently

There are many ways, but I prefer to manage it manually with ifup and /etc/network/interfaces.

Edit /etc/network/interfaces. Feel free to use DHCP instead of static IP.

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auto lo
iface lo inet loopback

# wlan0
auto wlan0
iface wlan0 inet static
    address 192.168.1.100
    netmask 255.255.255.0
    gateway 192.168.1.1
    wpa-driver nl80211
    wpa-conf /etc/wpa_supplicant/wpa_supplicant.conf

Then install ifupdown and use it to bring up wlan0

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sudo apt install ifupdown
sudo ifup wlan0

That’s it.