https://www.linode.com/docs/tools-reference/tools/find-files-in-linux-using-the-command-line/
find /home/username/ -name "*.err"
find and remove older than https://www.howtogeek.com/howto/ubuntu/delete-files-older-than-x-days-on-linux/
find /path/to/files* -mtime +5 -exec rm {} \;
find . -name testfile.txt #Find a file called testfile.txt in current and sub-directories.
find /home -name *.jpg #Find all .jpg files in the /home and sub-directories.
find . -type f -empty #Find an empty file within the current directory.
find /home -user exampleuser -mtime 7 -iname ".db" #Find all .db files (ignoring text case) modified in the last 7 days by a user named exampleuser.
find /<directory> -newermt "-24 hours" -ls
find /<directory> -newermt "1 day ago" -ls