Google My Business Link
If you have ownership of your business in Google My Business you can get your g.page link.
Head over to Google My Business Console
Scroll to the bottom of the Home page and click on "Share your Business Profile"
Google Maps Link
You can also fetch your Google Maps share link and use that:
Go to Google Maps
Search for your business
Click on the "Share" button
Google Place ID
A place ID is a textual identifier that uniquely identifies a place.
Place IDs uniquely identify a place in the Google Places database and on Google Maps (more info can be found here).
Examples (the length of the identifier may vary):
Place IDs are available for most locations, including businesses, landmarks, parks, and intersections.
Place ID Finder
watch this video tutorial or use the place ID finder by Google to find your place ID and to use it with your Reviews Notification.