Speak to your attorney, unless you filed the case yourself. A simple motion to voluntarily dismiss your case will suffice. In many jurisdictions, the court provides a template for such a motion, required by local rules. Contact the bankruptcy court to determine if such a form is available for this purpose.
Best of luck.
If you are at the early stages and your Chapter 13 has not been confirmed yet, simply not making your Chapter 13 plan payments and/or not complying with the trustee's objections would cause your case to not be confirmed. If you have already had your plan confirmed, then you can stop making the plan payments, and the trustee will eventually file a Motion to Dismiss for your failure to make plan payments.
Bankruptcy doesn't have an official form for every type of pleading. Most legal documents are individually crafted by the attorney representing a party, and a motion to dismiss and an order dismissing a Chapter 13 case are examples of pleadings that must be individually prepared. You may be able to find an example of this motion and the proposed order on some of the forms sites, but it is not a pre-printed pleading form like the petition & the schedules. Hope this perspective helps!