Replace the damaged glass when the window can stay
The frame is the fixed outer structure. The sash holds the glass and may open for ventilation. If both remain sound and the glazing system can be serviced, replacing the glass may preserve the existing window, trim and room finishes.
For an insulated window, damage to one pane usually means assessing replacement of the complete sealed glass unit. Its construction and dimensions need to suit the existing sash; visible glass measurements alone are not ordering measurements.