The process of old ceramic tiles removal and reinstallation involves the following steps: 1. Removing the old tiles using a chisel and hammer or a tile removal tool. 2. Cleaning the adhesive and debris from the subfloor. 3. Ensuring the subfloor is level and clean. 4. Applying new adhesive to the subfloor. 5. Laying the new tiles. 6. Grouting the tiles. This process requires proper preparation, attention to detail, and tools such as a hammer, chisel, tile removal tool, adhesive, and grout.