1. First import the picture, click "Bitmap" - "Outline Tracing" - "Line Drawing" in the menu bar.

2. Then the properties on the right can be adjusted according to your own requirements. Generally, the default is fine. Click "OK".

3. Then an outline drawing will be automatically generated on the original layer, click and drag it out with the mouse.

4. Then double-click the "Outline Pen" in the lower right corner and set the width of the outline to "Thin Line".

5. Then click "Colorless" in the upper right corner to clear the fill color of the picture, and the conversion of a picture to line draft is completed.