Can my internet provider know what I am doing on the internet (details inside)

I’m currently not living at home and I have to use an internet connection of a school. Every time I go to the internet I have to enter a certain ID and password. Each person’s ID and password is unique, and probably no one can use others’ ID and password.

It makes me wonder, is the internet provider watching each user’s activity on the internet? Do they know the websites I visit, the keywords I search on Google, the files I download, and even that I’m typing here asking if they are tracking me? I guess so, since this is a school and they need to keep their students in line, but I need solid proof.

Just curious.

I have been wondering about how public networks work, but I was motivated to ask this question when one friend claimed that they don’t know anything apart from who goes to the internet at the moment.