Can I still go to Singapore to work the night shift when I am 40 years old?

Of course. According to relevant public information, there is an age limit for working abroad. In Singapore, the age requirement is 18 or above, and under 35 years old, some highly skilled posts can be extended to 40 years old. RepublicofSingapore (English: Republic of Singapore), short for Singapore, formerly known as Singapore, Sin Chew or Sing Tao, also known as the Lion City, is an island country in Southeast Asia.