Wikipedia is a good place to look to find such information:

According to wikipedia, Stalker 2 was announced for a 2021 release.

However, this is a Ukrainian company.....given the state of Ukraine's economy and the prospects for a complete collapse - or serious heat up of the civil war, I would not pin my hopes on a release in 3 years.

FYI: The game is loosely based on a book by the Strugatsky brothers - famous science fiction writers from the Soviet Union. There is a movie - https://en.wikipedia.org/wiki/Stalker_(1979_film) and it is very good, though it helps to have read the book beforehand, or at least a summary.