As in the title?, ? According to the online search, the picture should be?

Serranidae, grouper genus, Epinephelus fish (I don’t know which one specifically)

The picture below shows the saddle-banded grouper Epinephelus lanceolatus?, commonly known as dragon grouper, gentian grouper, fish, catfish, catfish, deep-sea wild large grouper, gunhead grouper, horseshoe crab, mandarin duck carp, Purple grouper

It is the largest grouper fish, so it is also called the "King of Groupers". Distributed in the Indo-Pacific region, from the east coast of Africa and the Red Sea in the west to southern Japan in the north and northwest Australia in the south (except the Persian Gulf). Saddleband grouper can also be found in estuaries. It is produced in the waters northeast of Taiwan. This species of fish can grow up to about 2.7 meters (9 feet) long and weigh 440 kilograms.

Saddleband groupers usually live in caves or rock crevices along coral reefs, feeding on several species of marine life such as small sharks and small turtles.