If the files are already stored in OneDrive on the PC, then if you choose to install Microsoft 365 or Office 2021 for Mac on the new Mac mini, then signing in with the same Microsoft account would give you access to those same Office documents on OneDrive You would need to install OneDrive on the Mac and like WIndows, it is also part of the Office foer Mac installation.
If you are only concerned about transferring your Office files and not all of your other Windows files, then just put the Office files on a thumb drive and read them from that thumb drive on macOS.
Otherwise, the more involved Migration Assistant for which you need to install an appropriate Apple software item on Windows 10. See Move your data from a Windows PC to a Mac - Apple Support and from your Windows laptop download the appropriate migration tool for Ventura 13.*.
I also recommend that you take advantage of Apple's built-in Time Machine backup solution to a suitably sized (2 - 3x the internal drive size) external mounted drive. I happen to use Crucial's X8 SSD as they have proven rock solid reliable and very fast. You will need to use Disk Utililty to erase and format the Crucial drive to APFS instead of the exFAT formatting on it. Then in Settings > General > Time Machine, set that Crucial drive as the backup device. Time Machine will run approximately every hour your Mac mini is powered on.
Apple's iCloud is a convenience service, not a backup solution.