This is an error caused when you install from a package manager. Try running this command and see if you can run the wallet after:
ln -s /usr/bin/nodejs /usr/bin/node
After that changing nodes can be done by just typing
node nodes.iota.fm:80 (or any node you want to use)
Edit: I see your new issue, you forgot to actually run the IOTA-CLI.
I've provided ...