Not a stupid question at all!
Typically you would just be trying to put active opponents on a range. There can also be plenty of small pots you're involved in that don't use this framework at all.
For example, suppose I raise pre-flop with 99 on the button and the big blind calls; then I bet a 2 5 8 flop when checked to. Up until that point in the hand, I'm only giving some subconscious thought to ranges. It would only be if my opponent calls or raises the flop bet that I would start trying to explicitly put him on a range.