With regard to your device, a website knows your device type, what browser you are using and the browser language on which you can dedicate the user's language. Other information includes your OS and whether you have cookies enabled. For example, with this information you can set a language for a website without asking the user what language he speaks.
You are on a mobile device using the browser browser, and you speak german.

Your battery status shows how much battery you have left, whether your device is charging and how long it takes to charge and discharge. This information can be taken to reduce the websites color brightness if it detects that the user is low on battery.
In your case, your battery is fully charged.

Your location can be retrieved based on your IP adress. Thus without the users permission the website only knows where the internet provider of a user is located. However, most of the time, this information also fits to the user's location.
Based on your IP adress your internet service provider is and is located in , .

Of course, a browser can always detect where you keep your mouse, how many times you click and on what object you are clicking. With this information the whole webdesign could be adapted to your intuituve mouse movement. For example, if a user sticks to the right side of the page, maybe due to having a second screen connected, all clickable content can be placed on the right side as well.

In your case, during the use of this website you kept to the middle of the page and you used your mouse to click times.