Earn on what you most understand yourself. For example, I am interested in football and always look for the information I need on https://777score.com/ here I also get predictions about the outcome of future games and only then I make my sports bet.
I think you should choose variant in which you have good experience. As for me I prefer sport betting, it is much more simple than trading. If you are a beginner I can recommend to make some bets for example on boxing https://thebossbet.com/boxing/ then you will understand all principles and rules.