I think you are referring to Binary Options and most have 60 seconds expiry time. There are a few like FortuneJack or Secondstrade. Search the forum for those. But they are risky.
i heard there ia like 50% chanse to win
It depends on house edge. You will never get 50% odds considering the casino has to make money.
Yes, it is very hard to get 50% chances to win. It is just a pure gambling and one can win only based on luck.
FortuneJack is more reputed site in this forum so you can try to check there site. Good luck to you.