If you have an internet connection, this small tool identifies and downloads only the specific files your system is missing. Download: DirectX End-User Runtime Web Installer How to Install DirectX 12 Offline on Windows 10
Because DirectX 12 is integrated into the OS, Microsoft does not provide a single "DirectX 12.exe" installer. Instead, you use redistributable packages that include all necessary components for Windows 10 64-bit: directx 12 windows 10 64 bit offline installer link
If you are using the June 2010 redistributable for an offline installation, follow these steps: If you have an internet connection, this small
the 95MB+ package from the Microsoft Download Center. It will ask for a location to extract the files
It will ask for a location to extract the files. Create a new folder (e.g., C:\DXTemp ) and select it. Open the folder where you extracted the files. Locate and run DXSETUP.exe . Follow the prompts to complete the installation. Verifying Your Current DirectX Version
To check if DirectX 12 is already active on your 64-bit system: How To Download & Install DirectX 12 (Windows 10 & 11)