on apple tv do you have to pay for every station on tv you want?

The Apple TV box does not have included services.

• VOD services like Apple TV+, Netflix, Amazon Prime Video, HBO Max, Disney+, etc. will have to be payed for separately. Some of them may have free trials.
• Services like iTunes Store movies, VUDU, etc. will have to be payed for by title (buy/rent).
• Linear “Live” TV channels requires a plan with a pay TV provider. That can be an existing cable/satellite TV provider, or an internet streaming TV provider (YouTube TV, Hulu+Live, FuboTV, Sling TV, Philo, DirecTV Stream). Typically, these offer packages of dozens to hundreds of channels.
• Other streaming services may be accessible without a subscription plan (YouTube, Vimeo, Vevo, Twitch, TED, Classix, RedBull TV, Amazon Freevee, Crackle, Fawesome.tv, Kanopy, Pluto TV, etc.). Peacock TV and Sling TV have a free tier.

The Apple TV app offers several services, including in-app Channels, which are mostly VOD services like Paramount+, Showtime, AMC+, Starz, and some 30 more (in the US). Apple TV+ is also presented as such a Channel.

Each of these requires a separate subscription, and that subscription has to be started through the Apple TV app.

Subscribe to Apple TV channels in the Apple TV app - Apple Support

Apple TV Channels FAQ: Services, pricing, availability, and everything else you need to know - Macworld