In gambling, no can tell surely then can win money from their next bet because every game including sports betting need some luck to win money. So no one can say confidently they can win their next bet, but they can predict more accurately some sports results, but those also come with litter some risk.
No. There are odds. If the odds are in your favor and the potential gain is high, you place your bet. If the odds are not in your favor OR if the potential gain does not justify the risk, you don't go for it. Keep applying this philosophy multiple times and you will be winning above-average, above people who place bets based on intuition alone.