You should do as much research possible and read up until you fully know the concept of fixed odds gaming.
They can bet by numbers, like even or odd, by colors like black or red plus. With slots you have to press a start button and wait each time a winning combination hits the pay designs. https://kenhtingame.com/giai-tri/rikvip-huong-dan-choi-mini-poker-tro-choi-don-gian-vui-nhon/458393