When I hold a window to move it and i press my shortcut to change desktop, linux freezes.
It shouldn’t freeze ─ if it does, then that’s a bug ─ and it won’t be the entire system that’s frozen but only the Plasma desktop.
Either way, that is not the correct way for moving a window to another desktop. Right-click on the window title bar or on the task manager entry for that window and then choose “Move to Desktop”, or enable the sticky button on the window title bar, switch to the desktop of your choice, and then disable the sticky button again.
Same here, my KDE desktop and panels freeze randomly. But apps work fine as I can switch them with keyboard shortcuts but not through the taskbar.