Three commands cover most of the "put a file here" moves you'll make.
touch creates an empty file.
touch /root/notes.txt
If the file already exists, touch updates its modification time and
leaves the contents alone. That second behaviour is useful sometimes;
usually you just want a new empty file.
cp copies a file from one place to another.
cp /etc/hostname /tmp/hostname-backup
If the destination is a folder, the file is placed inside it with the same name:
cp /etc/hostname /tmp/
Copying a whole folder needs -r (recursive):
cp -r /etc/apt /tmp/apt-backup
Without -r, cp refuses to copy directories.
mv is both "move to a different folder" and "rename in place". Linux
doesn't distinguish, renaming a file is just moving it to a new name in
the same folder.
mv /tmp/hostname-backup /tmp/hostname.txt # rename
mv /tmp/hostname.txt /root/ # move to /root
Unlike cp, mv handles folders without needing -r. Moving a folder
just updates a pointer, so it's fast even for huge trees.