Stay In The Lane
Driving on highway at very fast pace is a dangerous job. One should be very experienced to be able to drive on highway.
Manufacturers are adding self driving mode in their cars. For doing same, they put lane-departure warning (LDW) and lane-keep assistance systems (LKAS) rely on a camera mounted behind the windshield to read the lane lines ahead and ensure a vehicle stays in its lane. LDW warns the driver by a voice or vibration, when a corrected action is to be taken. Whereas LKAS itself corrects the staring wheel so that car is in right position.
But for these systems to work you need to switch them on using buttons present on your dashboard. Always go through your manual before riding a car and be sure you are familiar with all the system.