To place bets, it is not enough just to know dota 2 well , you need to know how esports teams play, what is going on in this area in general , and if you want to make money on this, then you need to know everything related to esports.
My uncle does this and he taught me how to bet and always advised me, he recommended me
https://tips.gg/dota2/matches/ on which I bet so far. CS GO or Dota 2 is not particularly important, the main thing is what you understand more! For example, I like both games , but I only bet on Dota 2 , because I don't really follow what is happening on the professional csgo scene
And keep an eye on your money, dudes, don't bet too fast