Command to move files to Ubuntu trash for files older than:

ubuntu-trash-files-older-than.md

Command to move files to Ubuntu trash for files older than:

find . -type f -name '*.txt' -mtime +7 -exec gio trash {} \;

Where:

• find .: search current folder
• -type f: limit search to files
• -name '*.txt*': limit search to files that have .txt extension
• -mtime +7: last modification date is >= 7 days
• -exec gio trash {} \;: move matching elements to Ubuntu trash

Note: {} represents the elements and ; closes the command