Question Questions about multiplayer servers for mobile games.

Hi, I have questions about multiplayer servers for mobile games.

I have a basic turn-based multiplayer game in mind. By informing myself, I see that the prices are expensive for independent developers.
Then I would like to find out about the server and client method at the same time.

- What are the pros and cons of doing it this way?
- Due to the characteristics of the game I want to make, is this form applied well or badly?
- How does the server and the client work?
- Is it totally free to do it like this?


Thank you so much