You can play the video slots with a no deposit bonus. If you want to play any of the other games with a no deposit bonus, then you'll need to check out the terms & conditions for the bonus before you redeem it. Many of the online casinos restrict play to only the video slots, and if you attempt to play any of the other casino games, then it voids the bonus from your account. Some of the casinos will permit you to play the table games, but those games will not count towards the wagering requirements that you'll need to meet in order to withdraw your bonus winnings.
There are a few online casinos that will permit you to play some of the table games with a no deposit bonus, but the bonus generally comes with outrageous wagering requirements that will be difficult to meet. To play it safe, you should only take a no deposit bonus if you want to play the video slots or scratch cards. To play the other casino games for real money at any of the online casinos, you'll need to make a deposit.