Unlock your tablet and go to Settings > Wi-Fi;
Toggle the Wi-Fi switch to on;
Your tablet will automatically scan and list nearby Wi-Fi networks (sorted by signal strength);
Tap the name of your target Wi-Fi network, enter the case-sensitive password, then tap Connect;
For a hidden Wi-Fi network: Tap Add network at the bottom of the network list, enter the exact SSID (network name), select the security type, enter the password, then tap Connect.