If you buy Bitcoin with the intent to make money and selling most of it after, say, 5 years - then you don’t understand what Bitcoin is.
Most people don’t, and I don’t blame them.
reference
This is a reference post. Reference posts focus on giving you a good overview of a topic with resources and commentary to add missing details and nuance.
To understand the thesis of bitcoin, we must understand the money we have today.
It solves a problem you did even not existed.
In order to understand Bitcoin, one must first understand money, and to understand money, there is no alternative to the study of the function and history of money. - The Bitcoin Standard (Chapter 1)
You could just jump to the solution, but I wouldn’t recommend it. Go through this (how money works), then come again.