move files and directories to the parent folder in Linux

find . -maxdepth 1 -exec mv {} .. \;
this will move hidden files as well.

You will get the message:

mv: cannot move `.' to `../.': Device or resource busy
when it tries to move . (current directory) but that won't cause any harm.

https://superuser.com/questions/88202/how-do-i-move-files-and-directories-to-the-parent-folder-in-linux