"I do not have to do anything."
Translation:मुझे कुछ नहीं करना है।
With negative sentences, you can leave the hai at the end without sounding incorrect. Example:
Mujhe baat nahi karni (hai) [I don't have to talk]
Mujhe nahi jaana (hai) [I don't have to go]
However, it would be more grammatically precise (especially in written form) to include the hai
Also, note that the two aforementioned examples can also imply the meanings 'I don't want to talk' and 'I don't want to go' (respectively) depending on context, even though the more precise way to say that would be 'Mai baat karna nahi chahta' and 'Mai jaana nahi chahta'