The door opened and an old woman walked into to the Izakaya restaurant by herself.
An alive alcohol shop is a place that does a lot of alcohol. In Japan, these places are often izakaya, or, if you don't know Izakaya already from English, you can consider it to be a Japanese Style Bar.
The readings here are all kun'yomi, and rendaku turns the さか into ざか. If you know what an izakaya is already, it will help you to remember the reading.