When driving on the road, such as uphill, I lightly step on the accelerator, shift to second gear, and then should I continue to step on the accelerator?

You don't have to obey strict rules when driving. You should do whatever you want without violating traffic laws. Of course, experience is gradually summed up. For example, if your destination hasn't arrived yet, there are few cars ahead and the road is good, you can step on the gas and change to the third gear. If you are not satisfied, you can continue to shift gears as long as your car has enough power. In order to save fuel when going downhill, you can slide in neutral. In case of emergency, put your feet on the brake pedal, but don't turn off the engine. Novices should not slide in neutral. Let's talk about it when you are familiar with it. In short, driving is not a hard rule, but a feeling of flying freely. Please also study the traffic safety law seriously.