Can You Replace Just the Glass in a Window? Practical Answers for Homeowners

https://varimail.com/articles/how-to-fix-drafty-windows-and-cut-energy-bills-comparing-your-best-options/

Short answer: yes, sometimes you can replace only the glass. Other times the window sash, frame, or insulated glass unit (IGU) has failed and a full window replacement is the smarter choice