It all depends on the degree of your involvement.
Personally I manage to do my regular job and learn about crypto in my free time.
What is more, I plan to quit my current job and switch fully to crypto market because even despite its volatility it offers prospects for bigger money than I am now earning.
The opportunity to make huge money is almost over and people who invested in bitcoin and other alts when the price was really low had the opportunity to quit their job for good, but right now doing that would not be a good advice as you need to have a regular job and consider this as a part time investment like we invest with the stock market unless you are playing with huge amount of money there is no need to quit your job.