While it is impossible to give a firm answer to the question, it is clear that for every website that is free and accessible through search engines such as Google, there are thousands of other places on the internet that are not. Many valuable sources of information are hidden behind various layers of walls, including paywalls. While the estimates can vary widely, one study suggested as little as .03% of the internet was searchable with Google, while there are claims that only 1/25000th (.004%) of the internet had been indexed by the search engine (source). Whatever the number, we can set aside the myth that all anyone needs is a a computer and Google and the whole world of information is at your fingertips.
Good news: As a student (or staff member) in SD36 you can have access to many online databases and other district sponsored resources that other people have to pay for. If you are using a computer or other device within the district, you can use these without passwords. If you are at home, you will need usernames and passwords. Your teacher librarian can give you these.