Check the editor overlay, top left for the brush [3rd icon], then the pencil/pen [6th icon from left]. This pencil is also in the small toolbox. It brings up 'pen settings' [line size, mode, color, fill, etc]. Clicking it turns it on/off.
Dell Latitude 13.5" 2-in-1 Ubuntu/Win 11
Samsung Note Pro SM-P900 12.2 Android 5.0.2
Samsung S7+, Android 12
Samsung Note Pro SM-P900 12.2 Android 5.0.2
Samsung S7+, Android 12