In American English, both ways to say the year are correct. The difference might be in how we write the month and day. In American English it's usually month/date/year. In British English, the date and month are reversed. https://www.ego4u.com/en/cram-up/vocabulary/date/written

US: I'm more likely to say "twenty eighteen" or "two thousand eighteen." I am unlikely to say "two thousand and eighteen" but I would clearly understand it were someone to say it to me. But as everyone else has pointed out: To me and most other people in the US - 2/5/2018 ("two five twenty eighteen") is February 5.

1.Years There are three ways of saying dates after 2000, so the year 2018 could be: *Twenty eighteen *Two thousand and eighteen *Two thousand eighteen The first two are used everywhere, the third one only by AmE speakers. It isn't a big deal, though, and people will understand you whichever formula you use. 2. Days and months. This is more problematic. Some countries, such as China, put the year first when they're writing dates. Everyone else, apart from the USA, puts the day first. The American convention of putting the day after the month is extremely confusing for the rest of us. Everywhere in the world, 02/05/2018 is the second day of May. For Americans, however, this is the fifth day of February. This is an issue of culture, rather than language, and it as frustrating for native speakers as it is for non-natives. The only advice is that if you see a date referring to the first twelve days of the month, be aware that you have no way of knowing whether the '02' or the '05' refers to the day or the month. Unfortunately, you just have to use your common sense to work out which one is more likely in the context. https://en.wikipedia.org/wiki/Date_format_by_country

In British English, we use 'and' after thousand.

Americans do it the wrong way round, they start with the month, so today would be 9/11/19. Everyone else on the planet who is sensible does it day then month then year, so today is 11/9/19. Thats Americans for you.