You can link text, images, shapes and buttons. They can link to a section of your page, an external document, another page of your site, to the top of your page, another website and more. Here is a rundown on how to add them to your site.
When linking any text you need to highlight the text before adding the link option.
Once you have your text highlighted you then click the 'Add Link' button under the link tab in the properties panel (see screenshot below) and complete the options. See details on what options are available to you by viewing the other help articles in "adding links".
When linking a button, you do not need to highlight the text. Simply click on the button, which will display it's options. Then click on the link tab and choose where you would like it to link to. See details on what options are available to you by viewing the other help articles in "adding links".
Note that you can change the properties of the button, including its background (can be transparent), font, size, etc.
Save and Publish.