as title, i bought a CCleaner Professional 1year - 1 PC
ty
Yes you can do that quite easily,
Download/install CCleaner Free version to the new PC and then use your existing licence key to register/activate it as Pro.
You can download an installer for the latest version from here: CCleaner - Download Builds
As you only have a one PC licence you should of course then uninstall CCleaner Pro from the old PC.
You can still install and use CCleaner Free on that old machine if you want to.