How many continents are there?

It really depends on the categorisation one uses
Seven areas are commonly regarded as continents. They are (from largest in size to smallest): Asia, Africa, North America, South America, Antarctica, Europe, and Australia. On this basis, I’ve visited five – not having been to Antarctica or Australia.
As you’ll see from this analysis, however, there are at least six different ways of categorising continents with numbers ranging from four to seven.
In all the categorisations, one continent is Australia, but this continent is not always called Australia, sometimes being known as Australasia or Oceania.