If you use Gmail, Google as a search engine, Chrome or Google Maps, Google has access to a lot of information on your habits, information, hobbies, shopping preferences an so on. You can find out how much info Google has been collecting on you by signing into your google account (accounts.google.com) and then go to myactivity.google.com. This will show you your web activity by date, topic & service. Google is free so of course it comes at a price. You can stop Google tracking activity under Activity Controls and you can also delete by date or delete everything.
Be aware of your data and how its managed, try browsing in incognito mode, log out of your Google account when finished so as not to allow Google access to everything you do online.