Heat and Sauce Are So Confusionous

The only thing that matters in basketball is the last three minutes of the game. Heat and sauce are so confusing to me. How do how does one determine whether one is hot right now? Are they on a streak? Doing a heat check? You start out on the street, and then you do a heat check. Is there like, a meter at the bottom of the screen that kind of like goerner, if you can consider that a meter heat check?