Knowledge is a skyscraper. You can take a shortcut with a fragile fundation of memorization, or build slowly upon a steel frame of understanding.
by @Naval
First, the conclusion: fast is slow, and slow is fast.
Typical learning flow
Updated learning process
Advanced learning process
conclusion
There is no quick way, just as the introduction says: to conquer the skyscraper of knowledge, it is a shortcut to take the elevator. It will be more practical to climb to the top of the building starting from the reinforced concrete structure.