You can configure a free trial period for your plans in Chargebee. When customers subscribe to this plan, their subscription is created in the “trial“ status. At the end of the trial period, the subscription moves into “Active” status on successful payment.

The trial period for a plan can be set while creating it under Product Catalog > Plans > Create a New Plan, set the Free Trial field to the required number of days or months.

A subscription can have a maximum trial period of 180 months Or 5470 Days.

Related articles and documentation:
Trial management in Chargebee 

Subscriptions in Chargebee