To access presets / settings click the "cog" icon on the left side of the panel.
You can now select which type of setting you want to edit:
Presets allow you to define your own default styling for all elements, the site layout, colors, typography etc.
As you can see in the screenshot below we have selected the "Default" preset and apply it to our "Entire website" via the "Conditions" setting. You can set as many conditions as you want and there are various options for the conditions such as "Entire website", "Front page", "Post type", "Individual" etc.
You can create your own presets by clicking the CREATE NEW PRESET button.
Global settings apply to your entire site. They are organized in several groups as you can see below:
Page settings are page specific, precede your global settings and only apply to the page you are currently editing. They are accessible the same way global settings are by clicking the "cog" icon. You can reset them as well.
Template settings are only available when editing a template. There is an entire article about template settings: