environment variable edit error I have been trying to edit my environment variables. I referred to the sites but its not working. I should mention that I am very new to Mac
and I'm using it because my workplace has it. 
When I enter the command 

touch ~/.bash_profile; open ~/.bash_profile 


in the Terminal, it says

-bash: touch: command not found
-bash: open: command not found


though it did open the file once before.
First check that your path variable is working or not just type (echo $PATH) from terminal it will return the O/P like: /usr/local/bin:/usr/bin:/bin:/usr/sbin:/sbin 
if saying "commond not found"

Then you have to PATH variable to setup path variable below steps

1) vi /etc/paths 
it's will vi editor to edit type "I" and enter below mention lines

/usr/local/bin
/usr/bin
/bin
/usr/sbin
/sbin

2) press esc and type wq to save exit.