Stuck after Sequoia update supposedly completed

Force restart your Mac Studio by holding down the power button until it shuts off. This is a common macOS update glitch where the setup assistant hangs on a background iCloud or analytics sync, even though the actual OS installation is already successfully completed.

Follow these structured troubleshooting steps to get past the spinning wheel:

1. Force a Hard Restart

• Hold the power button on your Mac Studio for about 10 seconds.
• Wait for the computer to turn off completely.
• Wait 10 seconds, then turn it back on normally.
• Log in; your Mac will likely boot straight to the desktop.

when doing this, disconnect any connected external peripherals

Pippiwawa wrote:

I just installed IOS Sequoia up from Ventura on a Mac studio with M2 processor. After it was done I started it and entered my password. The next screen displayed the message "Software update complete" with a continue button. I pushed it and a wheel keeps spinning but nothing happens. Stuck. Any idea what to do about this?stuck after Sequoi

You can always force quit a shutdown by holding the power button/TouchID for ~6-10 sec.

ref: Force Shut down your Mac.

Log out, sleep, wake, restart or shut down your Mac

Shut down or restart your Mac - Apple Support

Reboot the mac and see where you are at.