Android's USB tethering lets you reliably share internet from your phone, but it may fail sometimes. Here are some quick fixes to get it working again.
To control your Android phone with your PC, you can use apps like Microsoft Phone Link, Pushbullet, Scrcpy, AirDroid, AnyViewer, TeamViewer, and Vysor.
Press and hold the PS and Share buttons on your DualShock 4 until it enters pairing mode (shown by the flashing white light bar on the back of the controller). Open your Android phone's Settings app.