Hello Moon Park
1. If you are seeing the toolbar as below,
where the sketch option is integrated into the design section.
If you want the sketch option to be separate with constraint-based sketching, please go to SpaceClaim Options>Advanced, if you enable "enable constraint-based sketching) the Sketch tab appears (Restart required).
Please let me know if you are referring to this, or if you are not seeing sketch options altogether.
Regards.
You are navigating away from the AIS Discovery experience