Question

a body with 500 gram in air this object is freely immersed in water state whether it will goes less in water or more in water give reason

Answer 1

In short :

The object will get lesser because of the buoyant force of water.
 
In detail :

The object will get lighter because if the buoyant force of the water. The water exerts some force against the object. So, the 500-gram object will become likely of about 450 or less according to the depth of the water.

BEWARE : The values I've given here are not accurate. They are just for an example.