Since I joined the crypto market. My gain is zero. I only have experiences and lessons. Does that have been called successful?

It happens at all. First you try, you make mistakes, you learn from mistakes, and then you know how to behave in certain situations, when it is better to hold coins, when it is better to sell them. What coins are better to buy, what to sell. Everything comes with experience.
It is normal if we are not gaining for 3 months as for sure we still have some stuff to do and bitcoin at that time is not yet our priority and we are still in the process of studying things out. It is okay just make sure after 3 years that we have already property and we are already rich that time.