I thought the purpose of restart or shutdown is to clear the computer's memory so I can start over. Thank you for your response.
That's how it should work. Unfortunately, Microsoft insisted on taking away your ability to control updates to Windows 8/10. As a result, the computer will often reboot on its own after an update. People complained that they were losing work during these automatic reboots. What you're seeing is Microsoft's "solution" to those complaints. Windows tries to put the computer back to its pre-reboot state after a reboot. Including starting up all apps and browsers and tabs that were running before the reboot.
If you don't like this behavior, you can turn it off:
You can also set Windows Update to not reboot automatically. It will instead notify you when it needs to reboot to finish an update. Note that I haven't found this to be very reliable - I set it to notify me but it still occasionally reboots on its own.
I can also tell you that private/incognito browser tabs do not reopen after a reboot. Which makes these automatic reboots really annoying for me since I almost always browse in incognito mode.