1st Option:
1 file whose contents are defined by the variables attached to them (all data-driven either by flat-file or D😎
index.php?mode=support
index.php?mode=products
2nd Option:
separate files for each main item.
Then define the data on the support page, or product page using variables in the URL
support.php?mode=contact
or
support.php?mode=knowledgebase
products.php?category=1
or
products.php?category=1&product=456
Either of these options generally meet most, if not all, of my needs when it comes to designing the framework. Templatize it as much as you can. It make everything easier from a design standpoint.