I know that earlier on in the process you noticed that buttons were not opening in a new tab. Wordpress Gutenberg, the new page editor, has not added an option to do that yet while keeping the button looking the same in the backend/page editor. Below I have added steps on how to make buttons open in a new tab. On the frontend (what the public will see) the button will still look the same, but on the backend (page editor/dashboard) it will just look like HTML. 
Here is a button as normal, without the '_blank' new page option:

Under the button options, select 'Edit as HTML':

Now edit the HTML to add the code target="_blank" as shown, and save:

Clicking the button will now open in a new page.

The way to make links open in a new tab is similar: if you click on the link in the backend, and click on the three vertical dots for more options, then clicking/enabling the open in new tab option. The button will then turn blue. Then update/publish and the link will now open in a new tab. If it is always a good idea to double check even if the icon is there.

If you have any other questions let us know.

Web Department, Diocesan
877-923-0777