Adobe does not offer a permanent "free" version of Premiere Pro 2020. However, there are two primary legitimate methods to use it without immediate cost:

A compatible graphics card with at least 2GB of VRAM (4GB recommended) to handle hardware acceleration. Enhancing Your Free Experience

Premiere Pro 2020 is more hardware-intensive than earlier versions like 2018 or 2019. To run it smoothly, your system should meet these standards: 64-bit Windows 10/11 or the latest macOS.

If you have an active Creative Cloud subscription, you can install specific older versions, including the 2020 release (v14.x), through the "Other Versions" section in the Creative Cloud Desktop app. System Requirements for the 2020 Version

You can download the full version of Premiere Pro from the Adobe website for a 7-day trial period. This gives you access to all features, including AI-driven tools, with no charge until the trial ends.

Minimum 8GB, but 16GB is strongly recommended for HD video, and 32GB for 4K/UHD content.