If you flick downward slightly above the keyboard it will disappear. Sometimes you can also tap the screen outside the keyboard and it will disappear. Maybe depends on the app. To select text long press on the text and then it highlights that text and reveals the handles to drag and select additional text. https://video.nostr.build/d819fbbc67a72c86b7b516562d733af2d6c0173b74c548167de12b8807924731.mp4