@DoublerHunter, if you just start playing, you may find it useful.

But after playing a few thousand hands, you will know the odds without even think of. And in most cases, you need to know approximates. E.g. AK vs AQ ~75%/25% without bothering for perfection. Those are called basic preflop odds. 

If you really want to progress, check some advanced stuff like GTO Poker Strategy. Here is a brief intro: https://www.pokerstarsschool.com/strategies/an-introduction-to-gto-poker-strategy/1711/