How do I enable 5GHz Wi-Fi on my phone?

If you wish, you can force your Android device to connect to Wi-Fi hotspots using the speedier 5 GHz frequency band. Tap Settings > Wi-Fi, tap the three-dot overflow icon, then tap Advanced > Wi-Fi Frequency Band. Now, pick a band: either 2.4GHz (slower, but longer range) or 5GHz (faster, but shorter range).