You can edit texts of pages directly in the website template.
If you see a dotted area with feather icon - you can click on feather icon and start editing the text.
Use the tool bar to change style, size and color of fonts.
If you see an area with Read more button - you should click on the button and edit full text in a pop-up
After editing just close the pop-up. Additional text will be visible in the READ MORE link.