Can I get a frame of my video to make a thumbnail? Absolutely!
Hover over the suitable frame on the timeline with the cursor, right-click the timeline, and click the Export Frame button. Now, you can get this frame and save it to your computer.
You can use it to be the cover/thumbnail when you upload this video to other platforms. Extremely easy!
Note: This feature is not currently compatible with Safari, so it is recommended to use Chrome.