You need to install rootsh or ssh to get root access by typing sudo gainroot (or root@localhost & p/wfor ssh). Although, "root" by itself might work - I can't remember.

*Beware*
Being "root" is akin to windows' administrator. The normal status is "user". In linux you have to actively become the root user and it turns off as soon as you close the termiinal. Being the "root" user gives you access to your whole device so be careful.

You cannot search all directories as "user", more are accessible as "root". But, it looks like you need a visual file browser. Much easier.
If you want to know which userspace you're in at any given moment, type "whoami".

ps. RD mode is BAD. I've written code on the device, have it OC'd etc,etc. And, there's been no need to go Red so far and I hope there never will be!