The reason a needle sinks but a ship floats is due to buoyancy.
A ship basically displaces the weight of the water due to design while a needle does not have the design to allow the needle to displace the water.
Another example would be a brick that is square and not designed as a boat is to displace the water so although the ship weighs more than a brick the brick cannot displace the water by design.
The ships design is what makes it float on the water even with all the weight it weighs and the weight it carries.
If the ship was just designed like a brick then the ship would also sink.
The buoyant force depends on how much water an object displaces.
But the weight of the water it displaces is more than the weight of the aircraft carrier, so it floats.
The upthrust force depends on the density of liquid whereas the weight of the body is related to the density of the body.
Complete answer: Water is impossible to compress.
Therefore, the ship floats but the needle sinks are all because of the surface area of the body.
Also the air that is inside a ship is much less dense than water.
That's what keeps it floating!
The average density of the total volume of the ship and everything inside of it (including the air) must be less than the same volume of water.