Checking via WiFi whether the door is locked (on the lock) - possible on the old lock?

I would be interested in a solution by means of which it would be possible to check whether a given door in the house is closed or open (I mean more precisely whether the lock is turned or the door is locked - exactly the upper one). .
I've tried looking for solutions like this, but I don't know how. My brother suggested buying a tiny sensor, mounting it on the lock pins going into the lock slots and connecting it to some kind of programmable board. A camera is obviously out, as it won't do anything.
If there are any ready-made solutions like this, e.g. along with locking and opening doors, then please provide some links or models.
However, it would be best if it could be done on what is there (I am attaching pictures of how it looks).
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Ideally it would also run on batteries or some sort of replaceable battery.

I found something like this:
Google - ABUS CFA3100 W .
but I don't know if there is control here via WiFi (Android app) and if it would be possible to mount it on this gerd . This would be the best solution.

See for example here: Link .

Thank you for your interest and I apologise as I did not specify and used colloquial wording. I meant more specifically to check if the door is locked. .

A simple switch mounted in the door frame is sufficient to detect whether the door has been locked. The question is how you want to present this information. A light at the door, the ability to check the status of the door via an app, etc....

NP: Sonoff SV Gate door GATE 5-24V reed switch
https://allegro.pl/oferta/sonoff-sv-brama-fur...MIxMqenZCt8AIVAWgYCh3Tewh4EAQYFSABEgKIq_D_BwE
Replace the reed switch with a switch
You can power it e.g. from a rechargeable battery or batteries
I just don't know how much current it consumes and how much you can run on it. A typical sensor adapted to work on a battery would probably be better. I do not mention typical alarm detectors which can work on a single battery for over a year because of the costs associated with the entire infrastructure needed for their operation. Although if you wanted to fit an alarm on occasion.... Maybe my colleagues will suggest something sensible.