For Nokia 225, FB is an app, created proprietory for the Nokia 30+ series OS, not a browser pointed at FB. I don't think you can remove the app from non-java phones like 225. You can surely move it to the bottom/corner as you wish..
Yes, this mobile has German installed as the operating language and can be set to German in the menu under Settings > Time and language > Phone language.
Yes, German is available as the operating language for this device. The Nokia 225 (2.40", 0.30 Mpx, 4G) supports German as the language for the user interface.
The hands-free car kit basically works with the Nokia 225 4G, as the device supports 4G and Bluetooth, which is a prerequisite for many hands-free car kits. However, there are reports that there may be limitations with certain models or systems. Official instructions recommend that the phone should only be installed in the vehicle by authorised personnel and that the vehicle or accessory manufacturer should be consulted in the event of problems.
A separate Bluetooth hands-free kit compatible with Nokia phones can also be used to make hands-free calls.
To summarise: A hands-free car kit can work with the Nokia 225 4G, but it depends on the vehicle and hands-free kit. If you are unsure, you should check compatibility with the vehicle manufacturer or hands-free system provider.
Large SIM card does not work and I think you could turn off the BT. However, one should not have high expectations of the device. It's cheap plastic and the voice quality is subterranean compared to Nokia models from 20 years ago. At the time, I wanted a device that was as simple as possible ... but not at the price of non-existent quality in every area.
Nothing against Digitec, they were very obliging back then. But in my opinion, the name Nokia no longer stands for anything.