I would like to create a non deletable directory, from where i can create and move files from another location to this directory with read and write access ?
Since you want a non removable dir, where you can create, paste, write and delete files you need to set the parent of this dir with non-writable permissions, and the dir with writable permissions. just as above, but taking consideration of group and everyone:
~$ mkdir -p parent/mydir ~$ chmod 755 parent ~$ chmod 777 parent/mydir
This wont let mydir to be deleted for everyone but you. And will let create and delete files within mydir, since this one has write permissions for everyone.
Read this for information on file permissions and how to apply them https://help.ubuntu.com/community/FilePermissions