Navigate to macOS system preferences: Apple Icon on the top left corner → System Preferences

Select "Security and Privacy" from the available options

Select the "Privacy tab" and in the left bar list, scroll down to the "Screen Recording" menu

If the applications checkboxes are locked for editing you will need to unlock those options by clicking on the lock icon at the bottom left

After entering the correct username and password, check the Google Chrome checkbox

Select "Quit now"

Start Chrome again, access the nunify session, and select share screen.