Hello,
for your own website there are ready-made PDF24 widgets, for example to compress, merge or convert to PDF. You embed them with a short code, and your visitors use the tool directly on your page: https://tools.pdf24.org/en/widgets
For automated processing on a Windows computer, PDF24 Creator has a command line: https://creator.pdf24.org/manual/11/#11-pdf24-doctoolexe
If you tell us what exactly you want to automate, we can say whether it is possible with PDF24.