Cracked window part

Hello! The cracked portion of your window is called the glazing bead. It's a long strip of plastic that installs on all four sides of the panel and it's what keeps the glass in place.

We sell a wide variety of glazing, which you can see here. Ultimately, you will need to remove an undamaged sample of the original in order to match up the appropriate size and shape. I'll share a video below that will go into more detail.