Here is the critical warning. Cybercriminals target industrial software because infecting a SCADA system can lead to ransomware payouts worth millions.
Siemens offers a of WinCC 7.5 SP2. This is perfect for students or engineers proof-of-concept testing. Siemens Wincc 7.5 Sp2 Download
Includes a REST interface for accessing WinCC tags and a Delta publish feature for WinCC WebNavigator. Here is the critical warning
Before looking for the download, you must understand why SP2 is specifically relevant. Released in late 2020, WinCC 7.5 SP2 was a major stability and functionality update. Siemens Wincc 7.5 Sp2 Download
S7-1500 certificates (TIA v17 - Wincc Explorer 7.5 SP2) - SiePortal