To extract .pak files from Unreal Engine 4, you can use a tool called UnrealPak, which is provided with the Unreal Engine editor. UnrealPak allows you to pack and unpack .pak files, which are archive files used by Unreal Engine to store game assets.
Here's a step-by-step guide on how to extract .pak files using UnrealPak:
1. Locate the UnrealPak tool: UnrealPak is usually located in the "Engine/Binaries/Win64" folder of your Unreal Engine installation directory. The exact path may vary depending on your installation.
2. Open a command prompt: Navigate to the folder where UnrealPak is located. You can do this by opening a command prompt and using the "cd" command to change the directory.
3. Extract the .pak file: Use the following command to extract the .pak file:
```
UnrealPak <path_to_pak_file> <output_directory>
```
Replace `<path_to_pak_file>` with the full path to the .pak file you want to extract, and `<output_directory>` with the directory where you want the extracted files to be saved. For example:
```
UnrealPak C:\Game\Content\MyAssets.pak C:\Game\ExtractedAssets
```
Note: You can also use relative paths if the .pak file and the output directory are in the same folder as UnrealPak.
4. Press Enter to execute the command. UnrealPak will extract the contents of the .pak file to the specified output directory.
After the extraction is complete, you should find the extracted files in the specified output directory. Keep in mind that some assets may be stored in a compressed or encrypted format within the .pak file, so further processing may be required to make use of them in your projects.
Please note that the extraction process requires access to the original .pak file, and you should only extract files from .pak files that you have permission to access and modify.