Flashing folder icon?

I have a Late 2013 iMac given to me by a family friend. I get to the boot selection screen fine and select efi boot. It starts and loads for a bit and gets to a screen where the apple logo is there and a bar at the bottom that says “about 29 minutes remaining”. It counts down for about 10 minutes or so then goes black and has a flashing folder icon in the middle of the screen and “support.apple.com/mac/startup” at the bottom.

Trying to upgrade to Sonoma.

Any ideas?

submitted by /u/JoeShtoops
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