The gearbox can certainly change gears with the help of synchronizers. After the shift of gears is full, we release the lever. At this stage, the clutch will get disengaged I.e, the clutch plate gets in contact with the Flywheel all over again. The generate is transmitted all over again https://waylonkbobn.blogdomago.com/31979254/getting-my-clutch-plate-to-work