RBoot explorer without root?

Can I use a root explorer without root so I can somehow issue a command from my PC to the cell phone that only gives the cell phone access to the data

Red is not so good for Samsung because the secruet by Knox Server almost notices that and I can no longer use most Samsung apps

So…

Can I use a Rott explorer with the help of a computer / laptop?

I want to change the "drawable in sytemui.apk"

No, of course not, do you think Samsung would put so much effort into their Knox, whatever if that could be cracked with a command from the computer?

Yes, you can also use other apps