Yes, all your traffic goes through your ISP's systems: can be servers, but it's also network devices.
It's not only what you are downloading, but also what you are uploading.
They can view all the content of your unencrypted traffic.
And they have metadata of your encrypted traffic.
Are you just wondering, or do you have a specific issue?
SANS ISC Senior Handler
Microsoft MVP 2011-2016 Consumer Security, Windows Insider MVP 2016-2019
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