Delete files by mtime:
find . -type f -mtime +5 -delete
The above command will delete files that are older than 5 days.
Move files by mtime:
find . -type f -mtime +380 -exec mv {} /path/to/dir/ \;
This will find the files that have a mtile older than 380 days and then it will move them to a new location. the ; is the way to end the command so that you can add more flags after the exec.