You might get lucky by calling qmake -set QT_INSTALL_PREFIX=... (https://doc.qt.io/qt-6/qmake-environment-reference.html). Maybe this doesn't work for Qt Creator, but then you'd only need to reinstall Qt Creator.

You should reinstall Qt to make sure everything works correctly. Some of the Qt tools - especially qmake - have the installation path baked in. They will not work right away when copied to a different directory. I believe there is a way to fix the paths. However, I cannot remember and I don't know which tools need fixing. To be safe: reinstall Qt in the proper location. It's way easier.