XF 1.5 Getting a certain thread's content in a template


Would like to preface this question with an open admission of how little I currently understand of templates: apologies for anything I have misunderstood.

I am picking up an addon which was made for me 2 years ago to allow me to have a completely "custom" page (no xenforo styling). I use this as a landing page, with buttons around the rest of my website (and also into the forum itself). This also allows me to use some xenforo variables, namely $visitor, allowing me to put the user's avatar in the corner of the page if they are signed in. Works great.

The custom page is created on my forum using a callback provided by the addon which changes the template to "PAGE2_CONTAINER" (arbitrary name?). I can then just stick the HTML in the template HTML.

I am now interested in retheming the site and was hoping to add some more onto the "custom" page - the latest news article. The news article is just the latest thread from a certain category, similar to how XenPorta's news module works.

How do I go about getting this thread's contents in another template? Variables?

Sorry if in my efforts to tell all the details I have made things exceptionally confusing. Thanks in advance for any replies!