A query may be possible via the browser. The applications on Android 8.1go are limited to the pre-installed ones.
There is also no real play store on this mobile.

Yes, you can. You have to be willing to tinker around a bit, but it is possible.

Either you install the "Aurora Store" via Bluetooth, which allows access to the Google Play Store (if you log in, you may be banned by Google, but you can do it without logging in), or you download the APKs directly via Bluetooth. It must be via Bluetooth, as the mobile does not have File Explorer and the browser blocks the installation.

If you have the Aurora Store installed, you can install pretty much any app. I currently have Twint, SBB Mobile, Spotify Lite (is more performant) installed on it. If you want to synchronise your contacts, you can do that too, have a look at DAVx5.

Hello, thanks for the feedback. What could be the reason that the map is not displayed in Maps? Viewing railway connections is possible

No, unfortunately not....

That's what I thought at first.

Gave my mobile to very grateful people in Ecuador... is now in use there with WhatsApp

No, nothing can be installed additionally. But WhatsApp is installed. Greetings