Assuming you mean an employer sponsored plan, contact your plan administrator to see how to access your account. If you have a recent (or not so recent) statement, there may be details there. Keep in mind, the ability to cash out of a retirement plan usually depends on your employment status with the company. You may be unable to cash out while still employed.
Oscar, your statement needs some significant clarification. if your at the tables in Las Vegas, all we will have to do is count your winnings. If you have left a former employer and would like to know the value of your retirement plan, then I would contact the HR department of your former or current employer to learn what steps you might have to take to understand the value in your plan. That value, by the way, may or may not be available to you if you have not met the requirements of a vesting schedule or if you are still employed at the firm where you held a retirement plan. If your comment is about an insurance policy, you may want to call your insurance agent and ask if they can provide you an in-force illustration. In any event, more discovery needs to occur to accurately steer you in the right direction.