Edit (advanced) customs fields on page template

OK I’m freaking out a little bit here 🙂 Step back.

I have to make some changes to a wordpress website (with a custom template) that I “inherited” from another guy, which developed it in 2015 and then moved to better and brighter roads.

Said website uses advanced custom fields (pro). I need to change some text / images in the homepage. Such text and images are stored in two custom fields. These two custom fields have a rule that say “show this field group if Page Template is equal to Home Page”. However, i cannot find this “home page” Page Template ANYWHERE. There’s a “template” menu item in the back-end with a “page” subitem, which however is empty.

If there are these custom fields, and if someone filled them in with images and texts, there should be somewhere in the back end the possibility to change them, right? But where? What am I missing?

Apologies if the question is basic or unclear!