To add content click on the "Add Text Content" button after which the following will appear:

The following are some of the options that you have in order to customize your text: 

The options for the text editor are, in order, 

Bold

This is bold text

Italics

This is italic text

Block Quote

This is a block quote

Numbered List 

1. This is a 
   1. numbered
      1. list
2. example

Bulleted List

• This is a
  • bulleted
    • list
• example

Insert Horizontal Line

This is before a horizontal line

---

This is after

Link

This is a link

when clicking the link button, the following page appears

 

Unlink

This will remove a link from any selected text. It will only work if the text that you have selected is a link, this is not for regular text. 

Remove Format

This will set the formatting from any selected text to the default, for example if I remove the format from the following text:

Test formatting

The text turns into:

Test formatting

Promo

(DOES NOT APPLY TO SUB-SITE PAGE)

This button allows you to insert a promo content that has already been created by searching, see this page to learn more about creating promo content

Testimonial

(DOES NOT APPLY TO SUB-SITE PAGE)

This button allows you to insert a testimonial that has already been created by searching, see this page to learn more about creating a testimonial

Number

(DOES NOT APPLY TO SUB-SITE PAGE)

This button allows you to insert a Number Callout that has already been created by searching, see this page to learn more about creating a number callout

Add Media

This button is how you add images, see adding images page here