1, first of all, in the mac computer, select "Local Items" "Password", you can see the Wi-Fi account is connected.
2. Double-click on the Wi-Fi account and put a check mark in front of "Show password" as shown in the picture.
3. You need to enter the system boot password, as shown below.
4, then the wifi password will be displayed, viewed successfully, as shown in the figure below is complete.