What is the api key where is talking about that?

API
1

What is the api key? https://api.twitch.tv/helix/users?login=AndreMatosdeSousa&apikey=24
and where is talking about that?

2

apikey is not a querystring parameter. If you are talking about a client id for accessing the API then the Apps & Authentication docs explain how to obtain a client ID, and OAuth tokens.

3

Thanks