Something wrong with adding constraints

6 edition of book
xcode 10.3

Before adding constraints (on page 14) the simple app looks good on the simulator. Once I add the constraint on the top text label, “horizontally in center” and run on simulator the label renders at the very top of the viewable area. I select the top label then add the constraint, but nothing I do seems to work. As far as I can tell I am following the book and tried many times.

There is no longer iphone 7 in xcode 10 that I see, so I am using 8.

Further when I try to add the constraints to the rest of the “views” on page 15, there is no option for “Align” in that dialog box. And even still the wording is unclear. “Select the four views…”, do you mean “Select the four objects” (the two labels and two buttons) or View objects? There is only one “View” as far as I can tell. The parent View. I’m already frustrated with this book and I am an experienced programmer.

What version of Xcode was the 6th ed. of the book written for?
If you are facing a compatibility issue, you can download older versions of Xcode from Apple developer site. But then you might encounter new compatibility problems, this time with the version of the macOS you are using.