1. Enter reading page -> Tools ;
2. Select Hyperlink on the toolbar, then you can drag a range for the link. The range is the area where the link is active;
3. There you can choose to redirect it to different destinations: Page, URL and Email:
1) Page: Enter a page number of the current document so that you can be navigated to that page directly;
2) URL: Insert a link to the destination web page;
3) Email: Provide an email address to send emails easily.
4. Click Go to finish the setting;
5. If you want to make the link area visible or invisible, click Page Display and turn on or off Highlight Links, or you right-click anywhere in the PDF and tick Highlight Links.