This is the inside of a medium size RO RO ship while in for service at a shipyard in Turkey.
Every now and then (normally every 3-5 years) a ship needs to go to a shipyard for service.
There they normally puts the ship in a drydock, where they pump out the water so the ship sits in a dry place where it can get service to the hull.
They sandblast the entire hull to remove old pain and rust. Sometimes they repair the hull by cutting out a piece and replacing it with new steel.
Then they prime the surface, before they eventually paint the entire hull with strong ship paint.
Other needed upgrades and services that can not be done while the ship is in traffic, is also performed while the ship is in a drydock.
This ship was among other, being outfitted with a scrubber system, to clean the exhaust gases. This way they can be sure to comply to the emission standards set by the maritime laws around the world.