Error Installing Homebrew - Brew Command Not Found

The warning is telling you what is wrong. The problem is that brew is kept in /usr/local/bin

So, you can try /usr/local/bin/brew doctor

To fix it permanently alter your bash profile (.bashrc or .profile in your home directory) and add the following line:

export PATH=/usr/local/bin:$PATH

Check XCode is installed or not.

gcc --version
ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"
brew doctor
brew update

http://techsharehub.blogspot.com/2013/08/brew-command-not-found.html "click here for exact instruction updates"