Extend/connect outdoor power line

It certainly makes sense for me to connect the cable to a small distribution box with an RCD, right? From there, I could continue to a socket column or even connect something via smart home control.

Then clarify that with a knowledgeable electrician. I am an IT specialist (software and projects), but I had an electrician as a father. Therefore, I have acquired some knowledge, even though officially many things are not allowed. What I do know is this: If you now put an RCD outside behind the one already present in the house, it is not necessarily guaranteed that it will trip first in the event of a fault. That then depends on the response behavior of the two RCDs, and that gets more complicated than inexperienced laypeople can understand. PS: At the point where the gardener extended the cable, the electrician could possibly rewire the 5 conductors differently so that the switch inside could be used. Provided, of course, that you can access this junction/extension.

Install a Shelly with WiFi/Bluetooth inside at the switch. You can then control it smartly by time or weather or also by button. Then everything just turns on/off. You only need to extend the line. You can't run 5 lines outside if you still have garage/bungalow/carport/gate/garden/pool etc. I will also only run 2 lines outside, one for the outdoor light/driveway and one to the carport with 10mm² where a subdistribution then takes place for the bungalow/garage/cistern and from the garage another subdistribution for the rear garden/outdoor sockets. That doesn’t work any other way with 50m line length from the house. In the subdistribution then a RCD/MCB.

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Since I have only dealt with electricity in a layman's way so far (connecting lamps) and currently have no idea how to lay electricity outdoors, I am turning to you.
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