Open Google Photos or your File Manager and search for 20210722 or check the "Videos" folder.
Use the search bar to look for VID_20210722_192642_254.mp4 . 3. Tips for Handling This Video
If you can describe what is in the video (e.g., "it's a birthday party" or "a sunset at the beach"), I can give you more specific tips on how to edit it or turn it into a highlight reel.
If this is an important memory, ensure it is backed up to cloud storage (Google Photos, iCloud, OneDrive).