It depends on the type of gambling a gambler chooses to do.
If you are good at sports, only do sports betting.
If you play poker, go for poker games only on casino.
If you feel you are lucky at dice games, there are plenty options and you may try crash games too.

The question is, how focused you are at building a career in gambling if that is what you want to do in your life for long time. If you can take small risks and have proper money management with good risk to reward strategy (you need it here too), then you can make a successful career in gambling. If you do not wish to gamble, there are other options too like creating a gambling website for a client, integration of crypto in it, providing customer support services and plenty other things to do to make a career in it without gambling yourself.