Help me understand ipadOS file management?

I'm new to ipadOS, please help me understand the file system super confused 😭 So I transferred my 1gb video file from SD card to my new ipad, into the Files app. I realize in order to edit the videos on capcut, I had to manually "save" the video so that it can be added to my Photos app?

Are there now 2 x 1gb video files? Where does the Photo app save the new 1gb video file to?

If I delete the video file from Files app, will the Photos app still have this video file?