What Ever you do it now just get better on this you don't need to search for things what to start just improve things what you have now.
I don't understand what you are talking about, how can someone become rich with a lot of money in a side job, as far as I know crypto is not a job, how do you say crypto is a side job, what do you mean.
Cryptocurrency as a concept is not a job but there are plenty of roles associated with crypto that can be defined as a job. You can be a blockchain developer, a market analyst/advisor, project manager, graphic designer, and many more. Crypto is a vast industry that requires different kinds of skills set. You can find an opportunity in every crook and cranny in this industry.