Want to enable the root account on your Mac? You can, but the functionality is a little buried in System Preferences. Here’s how to find it.
If you’re the primary user of your Mac, odds are you use an administrator account. This grants a level of permission required to do things like install software and change system settings, but it doesn’t give you permission to access everything. You can’t make changes to other users’ files, for example, or even see most of them. A root account can access everything.
Enable Root User Account
Open “System Preferences”
Now open the “Users & Groups” item.
In the “Users & Groups” window, click the lock at bottom left, enter your System password, and then click the “Login Options” link just above the lock.
Next, click the “Join” button next to the “Network Account Server” entry.
In the popup window, click the “Open Directory Utility” button and yet another window will open.
In the “Directory Utility” window, click the lock at the bottom left again, and then enter your System password (or use Touch ID).
In the menu bar, open the “Edit” menu, and then click the “Enable Root User” command.
You will be asked to create a “New Root Password” make sure you create a strong one that you can remember.
Log In As root
You’ve now created a root account, but how do you use it? By logging in as root. The login window, which you can access by logging out of your account or by using the fast user switching icon on your menu bar, will show a new “Other…” option. Go ahead and click that.
Type “root” as your username, and use the new password you created for root during “Enable Root User Account”.
Now you have logged as Root User and now you can install all those applications who were showing the message “You must be logged in as root when installing this program”.
Please copy the Application setup file in your USB drive or Documents folder and login from root user account and then access the Application setup file and install it on your macOS Catalina.
Please find the attached Video for more understanding.