Sure, I'd be happy to provide you with a SketchUp interior design tutorial on how to create a floor plan. Here are the steps:

Open SketchUp and select "File" > "New" to start a new document.

Click on the "Rectangle" tool in the toolbar, and then draw a rectangle on the workspace to represent the walls of your room.

Use the "Push/Pull" tool to extrude the rectangle upwards to create the walls of your room.

Use the "Line" tool to draw lines within the rectangle to represent the interior walls of your room. This will help you to create individual rooms within your floor plan.

Use the "Rectangle" tool to draw rectangles within your walls to represent the doors and windows of your room.

Use the "Push/Pull" tool to extrude the rectangles outwards to create the doors and windows.

Use the "Eraser" tool to erase any overlapping lines or surfaces.

Use the "Text" tool to label each room and each door and window within your floor plan.

Use the "Measure" tool to check the dimensions of your rooms and doors and windows, and adjust them as necessary.

Use the "Paint Bucket" tool to add colors and textures to your floor plan, such as different flooring or wall colors.

Save your floor plan by selecting "File" > "Save As" and choosing a file name and location.

That's it! By following these steps, you should be able to create a basic floor plan for your interior design project in SketchUp. Good luck and have fun designing!