When you ask somebody to do something in Japanese, you say TE-form verbs and then KUDASAI (Please, or I would ask you to). The TE-form verbs are the conjugated form of verbs that end with TE or DE.
When you want to tell others what they are not allowed to do, you combine the NAI-form of verbs and DE KUDASAI, and say NAI DE KUDASAI (Please don't do it). For example, let's say "Please don’t go." ...