There is only one continent called Europe, it is unique, so in normal use it would be uncountable. It could only become countable in certain unusual contexts, such as political discussions about the future of Europe, if two different visions of the future were proposed it might possibly be said "two different Europes were discussed" or 'I want to live in a Europe that is free and equal' - but this would be highly unusual and certainly for all intents and purposes Europe is unique and hence uncountable. Much the same could be said about World, if world is being used as a synonym for 'planet Earth' then it is unique and uncountable. However astronomers sometimes refer to some other planets as 'worlds' and so might use it countably, however this is also unusual, in general terms in is uncountable because it is unique.
If by English and Chinese you mean the languages, they are also unique and so uncountable, although occassionally you will hear English (and I suspect Chinese as well) used in a countable way if varieties or dialects of the language are being referred to. E.g. 'There are many different Englishes used in the world' again this is rare and it is normally uncountable because it is unique.
Finally 'Million' can be countable or uncountable. It used to be common to hear the number 6,000,000 referred to as 'six millions' but this is somewhat archaic now. But in an unspecified way million might be pluralised 'millions of people' and one million is often referred to as 'a million'
In summary I would say that all your words are normally uncountable, but, in unusual circumstances can become countable.