How to remove the extra part in the assembly in Solid works

You may have a multi-body part. Open the part that has the unwanted piece and check what you did. You can hide it or delete it. You need to make sure there are no relations between the parts or it will cause errors.
If it's simply another part you have in your assembly then delete or hide it.

You may have a multi-body part. Open the part that has the unwanted piece and check what you did. You can hide it or delete it. You need to make sure there are no relations between the parts or it will cause errors.
If it's simply another part you have in your assembly then delete or hide it.

To remove an extra part from an assembly in SolidWorks, you can use the "Delete" or "Suppress" feature. Here's how:

Identify the Extra Part: First, identify the part you want to remove from the assembly.

Select the Part: In the assembly, select the part you want to remove. You can do this by clicking on it in the graphics area or in the FeatureManager Design Tree.

Delete or Suppress:

Delete: If you want to completely remove the part from the assembly, you can delete it. Right-click on the selected part and choose "Delete". Confirm the deletion in the dialog box.
Suppress: If you want to temporarily remove the part but keep it in the assembly for future use, you can suppress it. Right-click on the selected part and choose "Suppress". This will hide the part from the assembly without deleting it.
Rebuild: After deleting or suppressing the part, rebuild the assembly by pressing Ctrl + B or going to "Edit" > "Rebuild". This ensures that the assembly updates correctly without the removed part.

Save: Save your assembly to retain the changes.