There are two ways to cut a video in Filmora, one is manual and the other is automated:
Manual:Import the clip in Filmora and select the split icon from toolbar. You can now trim the part you mean to remove by splitting it from the entire clip and delete that part of the video from toolbar.
Automated:Go to the Scene Detection function from the scene detection window. Click on detect and all the parts of the video will be seperated based on scene changes. Now you can delete the unwanted parts from the video as required.