Is it Ding Liren or Liren Ding?

also, is it wei yi or yi wei? dong long or long dong?

ding liren

Ding Liren

Wei Yi

Surname in front!

Then you should be Wong Jessie?

I am honestly confused

     East Asian nations almost all put the family name first, followed by the individual's name. Western nations do it the other way around. Often, East Asians will use the Western style when using a Western language. When East Asian come to Western countries they often use the Western style, and should they immigrate will sooner or later adapt that style permanently, almost invariably by the second generation. 

     You are right that that it can be confusing. It's considered correct usage to call someone who is native to and still lives in East Asia--such as Ding Liren or Kim Jong Un--in the East Asian style.

Chinese people who live in the West often adopt the Western (surname last) way of presenting their names, as it it is more familiar to their co-workers and friends. But Ding Liren is a native Chinese, so he puts his family name first. 

Also, many Chinese people living and working in the West adopt a Western-style "first name" that is easier for Westerners to pronounce. "Jessie" might not be the name she's called by at home.

Nikaru Hakamura 

Cagnus Marlsen

Ling Diren 

This happens with Vishy too.

Surname is almost always in front

It depends mostly on location. In China he would be called Ding Liren, but in USA he would be Liren Ding.

If its  western name then it is like "Jessica Wong", but if it is a Chinese name written in English it will be "last name" at the front, so Ding Liren

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