how to make something to a specific size in blender

To make something a specific size in Blender, press N to open the Transform panel, go to the Item tab, and directly input exact values in the Dimensions (X, Y, Z) fields for absolute sizing, or use S (Scale) then an axis (X, Y, Z) and type a number (e.g., S, 2, Enter) for relative scaling; remember to Ctrl+A > Scale afterward to reset scale to 1 for consistent operations.