You can use Magento for subscriptions. That includes subscriptions that start with a free trial period. However, it's not out-of-the-box functionality. You'll want to consider using a Magento Extensions such as:
Magento is a flexible and robust eCommerce platform. There are a tremendous number of reasons why it's the best fit for many eCommerce stores.
However, if you're trying to build a website for a startup with one trial/subscription, it's possible that Magento could be overkill, leading. You may want to compare to systems like FastSpring, Recurly, Chargebee, or Paddle, which you could integrate into a more basic website CMS.
Magento, on the other hand, will offer more flexibility and scalability, more eCommerce functionality beyond subscriptions, more integrations with 3rd party software and solutions, and a bigger ecosystem of experts and solution providers to support you.
Best of luck!