How to get feedback from relay 220V -> 5V?

Question

Arduino

Hey!
As a hobby, I decided to deal with the interaction of Raspberry / Adruino and electrical devices.
But I can't figure out how to get feedback from the relay. Let me explain with an example:
There is a non-latching switch, there is an impulse relay and a light bulb.
The relay can be triggered either by pressing the switch, or by the command of the Raspberry.
But in both cases, the Raspberry must receive the state of the relay (even if the Raspberry was turned off at the moment the button was pressed - get the state when turned on).
As far as I know, there are relays with two groups of contacts (one for the load, the second for the raspberry), but will they have 220V? Raspberry will burn from this.
I imagine it like this: when the relay turns on the load, a voltage of 3.3V or 5V should appear on the second group of contacts, and this voltage goes to the raspberry GPIO. Then you can at any time, even after rebooting the Raspberry, get the state of the light bulb (actually a relay). How to find such relays that have one group for 220, and the second for a weak current?
What other ways are there to decide what to read?
Thank you.

Answer 1

Using the second CONTACT GROUP is a possible solution, but not the best one. Firstly, there is a group under high voltage nearby, anything can happen. Secondly, extra contacts will seriously increase the cost of the relay. The standard solution to this problem is to use an optocoupler.