There are tons of apps out there, but some are just more secure and trusted, because they've been there since before QR was even a thing.
We're talking about Codex - QR Generator app.
This has also been chosen for its safety by well-known universities around the world, for didactic purpose, and one key-feature is that can operate completely offline.
The app lets you generate any types of QR with ease.
Generating a Quick Response code with your WiFi details (or for any other use see here) will be pretty fast with Codex - QR app.
URL, Text, Location, Phone, Message, VCard and more is ready to be created for free, in few easy steps.
Once created these QR Codes, will contain the infos you gave them forever, since these are created Static, you will not be able to edit them anymore then, but this also means, they will not require any internet connection to be generated and then, scanned.
This best-in-class app for creating QR Codes is available for Windows 10 and Windows 11 directly from Microsoft Store. It's currently the best you can use for anything QR.
Go, give it a try now here.