Aha!
To add to tt2's post, perhaps I can explain what has happened.
1. ... my screen looks totally different to yours see attached.
2. I might be a bit slow on the uptake I will not see 70 again, but i try...
I doubt it's your speed or seniority - iTunes is unbelievably complex. It has many ways of presenting the information to you, most of which you will never use. tt2's post has shown me something I'd not seen before - and I've been using iTunes daily for years.
Your screenshot shows you in the Artists' view, and your right-click menu shows options specific to that view at that time, which is effectively a view of all eleven songs on the Adele album. Here's the equivalent view of my Amy Winehouse albums (well, one's a single, but only you, me and tt2 know what a "single" is. Anyone under 40 probably doesn't):

Notice that like your picture, the right-click menu in mine also states Check Selection.
If we now look at the same artist in the Songs view (more on this view later), we see this:

And here's the point; un-ticked songs do not get played by iTunes unless you specifically select them to play. So, you manage to get a song playing, but when it finishes, every other song in the current selection (the rest of the album) is un-ticked, therefore will not be played - unless you specifically select it to play. Since there is nothing else to play in your current selection, iTunes stops.
This is correct behaviour. It's a useful feature (yes, really). The issue is that somehow, all your songs have become un-ticked. Don't worry (for now) about how that has happened - simply use tt2's suggestion (choose Check Selection) to put the ticks back. Going back to my first Amy Winehouse screenshot, if I click on Check Selection in the right-click menu and then look in the Songs view again, notice that the ticks are now in the boxes:

Hooray...
But now that the ticks are in the boxes, the right-click menu changes:

Notice that it now states Untick Selection.
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The Songs view:
I notice that your menu does not show the Songs option. If (and only if) you would like to have that view available to you, you can add it easily enough. In the second picture (in this post), notice the word Edit that I've ringed in orange. It only appears when you hover your mouse over the line that says Library. Click on the Edit button and you will see the following view:

Adding a tick to the Songs option will add Songs view to the list. The click on Done (which replaces "Edit" and will be shown all the time that you are in the edit mode.
Your Songs view might not look like mine, because I have selected further options in order to display additional columns. See what I mean about iTunes being complex?
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Final point - un-ticking songs:
Why - you may ask, is that feature useful?
Good question (I reply).
Among other things in my music library, are songs that are artist interviews and Monty Python albums (mostly speech). To prevent them playing - unless I specifically want them to, I un-tick those songs. iTunes skips them when playing. For example, suppose I don't want the remix version of Amy's Rehab to play, but I do want the other songs to play. I un-tick it:

Yes, I could have not imported it into iTunes, but then I would have fewer choices...
P.S.
tt2; if you've got this far. I hope you don't mind me suggesting that you might be over 40 years of age. I suspect you might be...