If you want to create a custom shape in Illustrator, you can use the Shape Builder tool. This tool lets you cut out a shape from a preexisting one. Here’s how to do it:

  1. Open the Shape Builder tool by clicking on the icon in the toolbar or by pressing Ctrl+Shift+B (Windows) or Cmd+Shift+B (Mac).
  2. Click on the object that you want to cut out and drag it into the window.
  3. Select the Shape Builder tool and click on the object that you want to cut out. The cursor will change into a crosshair pointer and start moving around the object. When you’re happy with your selection, release your mouse button.
  4. To finish cutting out your shape, click on the OK button in the bottom left corner of the window. ..