Floating ice will displace exactly as much water as it does when it melts to water. Ice that melts on a land mess such as Greenland and Antarctica will raise the ocean level when it melts.

Floating ice will actually increase the ocean a tiny bit as it melts into water because the ice has lower salinity than the ocean. Its comparable to around 3% of ice that melts on a land.

Only one way to find out... float some ice cubes in a glass of water and observe.

(Edit: I'm back to report the results. There was either no change in the water level, or a change below my measurement tolerance ;)

(Edit2: Here is a more serious take of that experiment: https://skepticalscience.com/Sea-level-rise-due-to-floating-...)

Ok that makes sense thanks.

Not sea ice obviously but there are places where sea level is "dropping" https://en.m.wikipedia.org/wiki/Post-glacial_rebound