A little simple geology and physics here. The ice in the Artic is mostly in the ocean, including ice shelves. The land under the ice is small scattered islands. The Antartic has large ice shelves projecting out from the continental land mass.
Most of this ice in already in the ocean. Like a glacier 90 percent is already in the ocean. The remaining 10 percent above water may melt and contribute to ocean levels. But, the 90 percent is already there.
Also, water, unlike most liquids, expands as it freezes and contracts as it melts. Therefore, the entire mass of ice will be less than it is now. Don't remember the coefficient of expansion (many years since college) but it should about even out. Only real major addition would be from land based glaciers.