Here are the Forza Horizon 5 System Requirements (Minimum)
CPU: Intel i5-4460 or AMD Ryzen 3 1200
RAM: 8 GB
VIDEO CARD: NVidia GTX 970 OR AMD RX 470
DEDICATED VIDEO RAM: 4096 MB
PIXEL SHADER: 5.1
VERTEX SHADER: 5.1
OS: Windows 10 version 15063.0 or higher
FREE DISK SPACE: 110 GB

Forza Horizon 5 Recommended Requirements
CPU: Intel i5-8400 or AMD Ryzen 5 1500X
RAM: 16 GB
VIDEO CARD: NVidia GTX 1070 OR AMD RX 590
DEDICATED VIDEO RAM: 8192 MB
PIXEL SHADER: 5.1
VERTEX SHADER: 5.1
OS: Windows 10 version 15063.0 or higher
FREE DISK SPACE: 110 GB