If you are looking to explore the software or work on a specific project, you can use official Siemens channels: Trial Download : Siemens offers a 21-day trial version

Step-by-step guides for installing TIA Portal V14 with specific packages like WinCC Comfort can be found on Siemens SiePortal . Tia portal V14 Setup - SiePortal - Siemens

The most straightforward way to ensure you're obtaining the software legally is to purchase it directly from Siemens or an authorized distributor.

V14 SP1 is required for compatibility with Windows 10.