Just like the same way the company has been doing, Apple will be giving people opportunity to watch the event on their devices. Apple TV, iPhone, iPad and Mac users will be able to watch it on their devices for free. Click on this link to learn how to watch it.
The Cupertino-based company is also planning to stream the event to Windows users too but you must be running Windows 10 and using the Microsoft Edge browser. The stream can be accessed by clicking on this link.