How can I add a hyperlink where there is no rich text editor?

In order to do this you need to edit, copy and paste the following HTML and place it where it is required.

<a href="https://www.ieg4.com/" target="_blank">The text that should be underlined goes here</a>

Replace https://www.ieg4.com with your URL. The bit that says target="_blank" ensures that this link will load in a new tab/window