wow64cpu.dll
This file is not a system component: windows itself, not a download. Restore it from the source that installed it rather than downloading a replacement.
Do not download this DLL on its own
Searching for a missing DLL by name leads to sites that hand you that single file. It is one of the oldest and most effective malware delivery methods there is, and a system DLL from an unknown source is indistinguishable from a deliberately modified one. There is never a legitimate reason to obtain a runtime component that way.
What it is
Part of the WoW64 subsystem, the layer that lets 32-bit programs run on 64-bit Windows. It is a core operating system file.
Where you see it: 32-bit applications failing to start on 64-bit Windows, usually after system file corruption or a failed update.
Run "sfc /scannow" and then "DISM /Online /Cleanup-Image /RestoreHealth" from an elevated terminal. Never replace this file by hand: it is tied to your exact Windows build, and a mismatched copy breaks every 32-bit program at once.
Why there is nothing to download here
There is no verified download we can offer for this one, because installing a file is not the fix. The steps above are what actually resolves it. That distinction matters: the sites ranking for this file name are selling a download that would not have helped even if it were safe.