The final result always depends on how many hours a person spends during the day practicing their drawing. From my experience, it takes at least about 1-1.5 hours per day starting off. Practice drawing from life, photos, draw from memory. In the beginning, you can start with simple objects such as cubes, cylinders, and spheres. It's better to start from these shapes because they form many objects. Then I recommend taking different classes to learn the drawing techniques of various artists, which helps you quickly come to your technique.