You only need to right-click Part 01 and select "Extract Here" (using WinRAR or 7-Zip); it will automatically pull data from all the other parts to recreate the full file.
It looks like you've shared a filename for a specific (Part 8) of a Forza Horizon 5 game download.
This specific version (v1.538.198.0) is an older build of the game from late 2022.
Typically, when you have files ending in .part01.rar , .part02.rar , etc., you need to keep in mind:
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