How exactly does Twitch work?

Can someone explain this to me? What are all the points, boosts, etc?

To stream or watch?

Both, but when you look at it there are a few things that I don't understand.

So as a viewer you have different options to support your streamer. For everything you do you get channel points, i.e. For following, subbing, donating and so on, but the streamer can determine whether and how many points there are for it.
Anyway, you just get points for watching, if you are a sub you get more.
You can redeem these points for things that the streamer chooses. Any actions, gifs, group access or whatever.

What does that bring the streamer himself? Does he get any money?

No, the channel points do not give the streamer any income.
These channel points are simply an extra incentive to be there, for example at esports stream (twitch.tv/ESL_CSGO e.g.) you can bet your channel points on the games that are currently taking place and even if the points have no value it is a little extra thrill.
The points give more audience loyalty and the viewer can imagine something if he has a million points or something.
At BIG Massa (twitch.tv/massa) you can e.g. Redeem a number of points (think 50k) to come to a special club to get a certain skin in your game (Trackmania) that you only get through it.
In any case, there's no money for the streamer, rather the other way around. At Prodigy, for example, you can choose one of 3 boxes for 666666 channel points that he opens and then you get the skin that is pulled out there. Yesterday someone won a flip knife Marble fade that costs ~ 350 euro

Yes

No, the streamer does not get any money from the channel points.

He gets money in the sense that the advertising companies can see how many people are watching the stream and for how long

This has absolutely nothing to do with the channel points because the streamer can decide how many channel points are distributed for what.
The numbers that matter to advertisers are followers / subs, and the average viewer.

Great thank you

The streamer does not get money from the channel points, but from the subs, donations, bits and advertising that is switched.

If a streamer meets certain requirements, he can become an affiliate. That means he can introduce channel points that you can use to buy fun little things, such as: B. An emote on his channel. You can also support him with a sub for 4.99 euro / month or so-called bits. You simply buy bits B. 100 pieces and can then z. B. Send a special emoji to the chat for a bit. The bit is then gone for you and the streamer gets 1 cent per bit. He can withdraw anything from 100 euro, which is quite high

So you have three people.

The streamers
The mods from the streamer
the audience

The streamers mostly just stream something like a game or themselves and just talk.

The mods are people who look in the chat det streamer whether people offend and can ban them accordingly.

The viewers watch the stream and can chat using the chat function.

I would be happy if it helped you.