Becoming a broker / selling crypto legally

I was a personal assistant to somebody who was a broker for crypto few years ago during the localbitcoins days. Things were going well for a while but something happened where the guy I was working for got involved in some sort of sting op where a seller of some crypto said it was connected to black market dealings and unfortunately the broker proceeded with the transaction and the seller ended up being government. I wasn’t involved at all and now the broker is doing acouple years in a camp. I would like to continue the business on my own but legally and not make the same mistakes. What do I need to do? What is required for a license? Can I just do it and not put myself in a scenario like that? Is it best to just leave it alone? If so, Is there any careers that would hire be based on this experience? I want to stay involved in crypto and make some real money but don’t know where to start.