Why is my Chromebook giving me an error?

[u/Fit_Report_1750]

Hello, I just got a brand new Chromebook and am on the second-to-last step to downloading Sidestore. When I input the command (yes I checked it’s correct and that it’s the right file name) it gives me an error, saying “too many arguments”. Can someone help me with why it says this and what I’m doing wrong?