Minecraft Support states that users need at least Windows 10 or macOS 10.15 to access online play and continue receiving updates through the Launcher. Windows 7 itself is no longer supported by Microsoft; support ended on January 14, 2020.
https://help.minecraft.net/hc/en-us/articles/42090028703245
Because of that, the “Face, fingerprint, PIN, or security key” Microsoft sign-in screen may not work correctly inside the Launcher on Windows 7, even if the account works in a browser. There may not be a reliable supported fix on Windows 7.