What does this mean??

Trying to install Monterey on a 2012 macbook pro 13" following this tutorial https://youtu.be/fyFqkbmKP68?si=IGzEZNipbQP5g8L5 Every time I get to this step it says this message rather than the completed download one, not sure what the issue is? I tried installing last night and got past this screen but messed up in one step so I had to restart (from the very beginning) Can anyone help me figure it out?? Also if this is important I am currently running 10.11.6, I have a 250gb ssd drive as the hdd, 8gb ram, and a 2.5 GHz Intel core i5 processor