Xilinx ISE Design Suite was the industry standard for FPGA development for over a decade. While it has been succeeded by the Vivado Design Suite for newer chips, ISE remains essential for legacy hardware like Spartan-6, Virtex-6, and CoolRunner CPLDs.
Click "Generate Node-Locked License." You will be asked to verify your contact information. xilinx ise webpack license
The hard part isn't the license. The hard part is convincing the 2012 software to compile a 2008 design on your 2024 laptop. Good luck, and may your routing times be low. Xilinx ISE Design Suite was the industry standard