Dash cams are typically mounted on the front and rear windshields of the vehicle and come with either adhesive or suction cup mounts.
While suction cup mounts may seem convenient and easy to use, they are not recommended since they can come off the windshield easily and are much more prone to vehicle vibration, which makes video footage shaky and blurry.
Almost all dash cams use adhesive mounts for good reason, as they are much more durable and reliable in the vehicle.