What is the best way to convert flac to wav on Windows 11/10 OS?

The following software can solve your problem, it is Online Audio Converter.This is an online software, totally free, without registration or payment, it can convert FLAC files to WAV format directly.

After installing this FLAC to WAV converter, you have to upload the FLAC file to the software so do something like this 'Choose files' to navigate to the location of the FLAC file to select it. It supports from the computer, Dropbox or URL to add the file, and then select the format of the "Output format" drop-down menu, select "WAV". 

Output format drop-down menu, select WAV, you can adjust the bit rate or sample rate (the default is to keep the lossless) point the green Convert button and wait for the conversion is complete.

After FLAC to WAV conversion is finished, click the "Open" button, the file will be saved to the download folder and finally open the file explorer, enter the download folder and double-click the WAV file to confirm that it can be played.