I had to replace the car battery in my 2009 equinox 2 days later when I drove home from Walgreens which is less than a half mile the car died. So many questions are is it a just a new car battery that is bad or is it the key fob has been dead so it drain the battery

 

A battery may fail due to no charging. You never had a dash message to service charging system? Usually the car will complain if there is an electrical issue.