@Klara Hi. Don’t worry about the English. If I understand correctly you are having issues with the QtWidgets.dll
Normally the way to solve this is to extract all the files into a new folder and make sure that QtWidgets.dll is extracted properly.
Sometimes Windows OS blocks external files, so please follow the steps on the following response:
However if you are using a computer at school or at a friend’s house, it may be possible that they have an antivirus or an extra permission setting is not allowing the software to unpack all the files, in that case my personal recommendation is to extract the program only once on a USB stick and run Pencil2D from the USB stick as this is possible mainly because you don’t have to install the software; it is portable.