It's a syntax problem. Thanks for putting in the exact text you entered, it helps greatly in seeing what happened.
It appears that you did not leave a space between DF0: and the word "to". So it's trying to open "DF0:to".
It's been a LONG time since I looked up the syntax for AmigaDOS copy but I think that your use of keyword ALL is the right idea, but again you need a space there.
I am sure that there were better ways, scripts to handle HD installation, but am not certain that they were included at the point that WB 1.3 was standard. I know my 1.3 machine was floppy based. WB 2 had a hard disk script I am pretty sure.
I think that the word "to" was optional. But if you just paste it back in and make it read:
DF0:c/copy DF0: to DH0: ALL QUIET
then it should work. PaulT1