An in5 subscription allows you to export your content as HTML5 from InDesign. 

With in5, you can create a layout in InDesign and export it as HTML5. The exported content is placed in a generated folder named "html5_output" that contains all the files needed for your content to appear and function in modern browsers and on a variety of devices.

After you export your content, then you would upload it to the web. Hosting is not included with an in5 subscription, so here are some materials that help explain the process of acquiring hosting, uploading content, and using free hosting alternatives: