First gear is so hard because of the unsynchronized nature of 1st gear. Another important factor that adds to the difficulty of the first gear is that the ratio difference between the first and second gear is too large.
Shifting gears can be easily achieved if the gears are synchronized properly, but it becomes very difficult when the gears are not synchronized.
You can shift from one gear to another by pressing the clutch pedal, but you should know when and where to change the gears of your vehicle.