concerns about install freebsd

I asked the question about "freebsd graphic text editor". The question  is
stupid.

The real questions for me(don't want waste too much time on install) would
be:

   - I already installed linux, any external pan drive needs to install
   freebsd?
   -  Can I install linux and freebsd in the same machine (I think it's
   intel x86 architecture)? If so, can I switch it easily, just use the
   shortcut key then switch to another system.
   -  How long does it take to install freebsd(all settings default, ignore
   internet speed) (I like to first make it work, then try to understand the
   system internals).
   - If all things are pretty easy to set, can you give an authoritative
   video link? (in case I fail, I can follow through) I know there are many
   youtube tutorials, but I obviously don't know which one is right.