There are individual button/call to action blocks for you to use in your emails and landing pages. Here is an overview of these powerful little blighters:
You can add buttons as sections:
And it will appear as a new section at the top of the left-hand preview:
You can add buttons as blocks:
And it will appear as a new block at the bottom of that section on the left-hand preview:
You can then edit either one. One edit button allows you to edit the text, link, text colour and button colour:
The other one allows you to align the button left, centre or right:
Just like any other block or section, at the top/settings level, you can edit, duplicate or delete it!