That answer depends on your ISP. It probably goes to a distribution box for your street, which connects up to a distribution box for your neighborhood, which connects up to your ISP, probably through many more distribution boxes.
At a certain point (probably the first or second distribution box), the signal goes from coax cable to fiber.
There are tons of different kinds of distribution boxes, routers, cables, technologies, etc for these networks, so what yours looks like is unknowable to any of us. Here are some examples of neighborhood or street level boxes:
Fiber:
DSL (landline phone lines) in a fiber junction box:
And then the higher level stuff would look something like this (I’ve never actually seen it, so this is just my guess of what it probably looks like, taken from a fiber supply company):
If you want to get a very basic understanding of some of the infrastructure between you and something on the internet, you can use traceroute. When I just did traceroute google.com, it took five hops just to leave my ISP, so that gives me a very basic understanding of how many levels my ISP has before my traffic gets out to the web.
Aw, they’re sharing their bottles of soda with each other. And it’s definitely not anything other than that.