Couple of things here:
1. Don’t use “sudo”. you don’t need it, you already have the permissions to write stuff in your own home directory.
2. You can easily view hidden files and directories in the graphical file manager by selecting View/Show Hidden Files from the menu. Or by pressing Ctrl-H.
3. You need to use the “-R” option in the cp command to copy a directory and it’s contents.
4. /home isn’t your home directory. /home/username is. So you are probably trying to copy from wrong place.
5. The shell is case sensitive, so ~/downloads and ~/Downloads are two different things.