Haven’t tried poppies yet in large enough quantities to feel anything, but I’d assume yes. Also similar to other mild natural drugs, like Khat or Kava or Nutmeg

Not really, you gotta chew a lot or drink a lot of tea to feel anything and then it’s more like drinking a few cups of coffee

It all depends a lot. There are different types of fragrances, for example an eau de cologne will smell less long than an eau de parfum which will smell less long than a “real” perfume. So depending on your day and type of fragrance you might need to refresh it during the day, or not. How much you use at a time can also vary quite a bit by person and smell. People who have been using a particular fragrance for a long time tend to use more since the nose gets blind to smells pretty fast. In general I’d say less is more here. Obviously the size of the bottle makes a difference as well. Finally, a lot of fragrances will not last forever. If you keep them too long they will spoil like the food in your fridge. Usually this takes a long time though.

To give you some concrete examples, a 100ml flacon of Brioni Eclat, which is an eau de parfum, will last me about two years. I use it most days, with one or two sprays per day. A 75ml flacon of a cheap eau de cologne I liked before that lasted less than a year, because it needed more applications. The shitty Abercrombie fragrance I used as a teenager started smelling funky after about 4 years of laying in some closet.