ruby - How do I install Rails on Windows using Development Kit? -

i'm new ruby , rails, i'm not confident install. when typed:

gem install rails 

i got response saying need update path , download development kit.

but, when enter:

c:\users\tim\documents\ruby\dk.rb init 

i error windows saying not recognise file type.

can easy understand solution?

per instructions, supposed type:

ruby dk.rb init