Windows has a built-in tool to repair missing or corrupted system files (though eutil.dll is not always a core Windows file, it is worth trying).
Reinstall the specific software that is requesting the file. If the software is a "hack" or "crack," be aware that the missing DLL is often a security measure by Windows Defender removing the injection tool. eutil dll download
C:\Windows\SysWOW64C:\Windows\System32