1. Open the WPSWord document, enter the editing mode, and click the "Insert" tab where you want to add the video.

2. On the Insert tab, locate the Media group, and then click the Video button. In the pop-up dialog box, you can choose to insert videos from local files or online video websites, and choose the appropriate method.

3. After inserting the video, you can adjust the size, position and style of the video. You can resize by dragging the border and move the position of the video by dragging.