Amateur question about editting homepage

I installed Drupal 8, your church theme, and it’s the first time I’ve used Drupal, but it’s not as straightforward as I expected.
I’m having problems adding content to the homepage as the ‘edit’ page is very unclear.
I get the following options:
Title ….. which is straightforward enough.
Image ….. again straightforward with alternative text box.
Link …… now here it gets awkward.
I can enter a link but under this text box it say’s “Start typing the title of a piece of content to select it. You can also enter an internal path such as /node/add or an external URL such as Enter to link to the front page.”

Well where doI start typing and how do I select it?
All I want to do is add content to the home page but there is no text edit box anywhere.
This is a little bit perplexing, can anyone help?

Drupal version: