Got to windows start and type run or type click
win + R
This will open up run prompt.
SystemPropertiesAdvanced.exe and hit enter System properties window will show up.
Environment Variables >> Path
click edit then new and paste
Save and Done.
Now you can use
atom . to open atom with bash or terminal.
_P.S : To know your atom version go to _
You will find your app folder with version with it.