There is a generator tag in the head of the document with the current version.
You can check it easily with:
curl https://meta.discourse.org -s 2>&1 | grep generator
Or by checking the same tag in the browser dev tools by pressing F12.
It’s easier to ask for links and then we can go and check the version in the link looking the the HTML. There are lots of non-technical users in here.
Yes.