Can I watch cable Tv without subscribing for cable? Just using internet service?

You would have to subscribe to a non-cable streaming TV provider, such as Hulu or YouTube TV.

I don't know of a way to to watch cable TV without paying for cable TV. Certainly not any legal way to do so. Sorry. For example, I watch Spectrum Cable through my Apple TV, using the Spectrum Cable via Apple TV, but I pay for Spectrum Cable. Quite a lot, actually. :-( But, these days, there's shortage of time to consume content, so cable has its place and that place has a substantial value on it! :-)

Good luck!

-- JDee