Dreaming of betting means you are at the stage of your life where you are taking more risks. Be aware that there will be setbacks as with any type of bets. However, as long as you are managing your risks properly, then you may be able to come out ahead of the game.
In general, dream about betting and gambling represents an aspect of your life that you are putting a lot of energy into. If you are having the same dream over and over again, then it is worth looking at this area and see if you can find a new path to success.
If you dream of gambling with someone and winning, it might represent you taking control of your life and succeeding. Or if you dream that a friend or family member is betting with you, it might represent your hope in them accepting the responsibilities.