Inno Setup installer script that can read a variable from the registry

Question

I am not a programmer, but a CAD designer. However, I need to create an installer for a database of 3D models for my employer. Browsing the internet, I chose Inno Setup. I am asking you for help.

Assumptions:

• the PATH variable contains data read from the Windows registry;
• the PATH variable always exists - it is the home directory of the program for which I create models, and the database with 3D models will be unpacked to a subdirectory in the program directory; however, it should be assumed that the installer script will check for the existence of the PATH variable;
• in the "base.ini" file, the DATE variable is stored, in which the database creation date is stored - format YYYY-MM-DD
• the database containing the 3D models together with the INI file is packed with a ZIP compressor - the directory with the models and the INI file has a specific name.

Scenario:

1. The user runs the EXE/MSI installer.
2. The welcome screen appears and the "Cancel" and "Next" buttons appear.
3. After pressing the "Next" button, another window appears: "Select the destination directory". By default, the PATH location taken from the Windows registry will be provided. The user can change it. At the bottom of this window we have three buttons: "Cancel", "Back", "Install".
4. After pressing the "Install" button, the installer checks whether the target directory exists - \program_directory\3D_models_directory. If it exists, it reads the base date from the "base.ini" file in the directory and asks to overwrite it. The date of the existing database, the date of the new one and the question about overwriting are displayed in the window. If there is no destination directory, the installer creates a new directory from the PATH variable and unpacks the entire contents of the ZIP archive into it. If the user chooses to overwrite, then the installer unpacks all files into the existing directory with 3D models and overwrites all duplicate files.
5. After a successful installation process, an information window with the "Finish" button is displayed.
6. At any stage of the installation, you can interrupt it with the "Cancel" button. Aborting the installation should be preceded by the question: "Are you sure you want to finish the installer with the database of 3D models? (YES/NO)".

Please help. Thank you very much for any suggestions.

Regards, Christopher

I tried to modify the script created by Inno Setup but I can't. I have no knowledge.