Telecommunication New Construction Semi-Detached House - What/When/How

My fiber optic connection also has a lead time of 5-6 months, I hope it will be ready by move-in.

What can I prepare here so that internet reception is guaranteed later in the finished attic/1st floor and on the terrace?

How is the connection via DSL generally made? Does a Telekom "socket" come into the utility room and does the router have to go there as well? I have planned to install LAN sockets in the children's rooms, the bedroom, the living room, and the attic. Does that make any sense at all?

First of all, one should provide a place for a network wall cabinet. Usually, the whole setup is placed in the utility room, where the Telekom socket (possibly fiber optic in the future) also goes. For the network cabinet, I would always tend to choose 19"; for a smaller installation, 10" also works. The height of the cabinet depends on what is supposed to go inside. Inside, you put a patch panel from which all cables in the house run out. Additionally, there is a switch, router, power strip, and possibly NAS.

Install double network sockets at all locations where stationary devices with LAN will or could be placed. For TV, possibly even 2 double sockets. Don't forget things like hobby rooms or garages (e-car charging station), or at least install empty conduits if you're not sure yet. Also, plan network sockets for WLAN access points. Best on the ceiling or high on the wall. No power is needed nearby, since some of the access points can be powered via PoE. The number and position depend heavily on the floor plan, but definitely plan at least one per floor. For WLAN on the terrace, the access point from the living area might be sufficient. You can also plan an outdoor access point, although a floor plan would be very helpful here. If cameras are supposed to be installed anywhere, then pull network cables there as well.

Thank you very much in advance for the many answers.

I think I still have a few general questions for understanding. I will describe it as I understand it. Please correct me.
The Telekom connection ends, along with the other media, in the utility room, in the form of the TAE socket.
From the TAE socket, a cable leads to the router.
The router is also located in the utility room. Does this also fit into a 10-inch network cabinet, or is it usually located outside?
Now I connect the router with a LAN cable to the switch/patch panel (I still need to read up on this, as I dealt with switches many years ago at LAN parties, but I have never worked with patch panels).

If I understand correctly, I can install a patch panel and a switch with 12 LAN ports in a 10-inch cabinet, meaning I can run a maximum of 12 LAN cables out. These will then be routed during the rough construction phase to the locations I planned. Do the cables then come out of the wall there? Or do they run in from "behind" into a network socket, into which I then plug a LAN cable from "the front" again to connect to the TV? Here I still have a problem understanding.

When you talk about providing additional network sockets for access points, how are these wired? Simply having a socket on the wall without any medium behind it doesn't help me at all. Or, as described above, do the LAN cables run from behind the wall into the server cabinet there?

To the network sockets that I want to install on the ceiling in the hallway on the ground floor and upper floor, can I then connect PoE access points that convert the LAN internet from the cable into Wi-Fi without additional power?

So, I hope you understand me and that I'm not completely wrong.

The termination of your connection via TAE is, as far as I know, still current (but related to copper; I have not yet dealt with fiber optic). Before that comes the ApL (see the same note), in a DH probably in one of the halves for both. Where do your availability statements come from? - for the second row I suspect you entered the existing addresses of the first row (?). In patch panels, everything is plugged in from the front and firmly connected at the back. They don’t switch anything themselves; this is probably mostly done here in the IAD (commonly "router"). The building owner services are your best contact; they are also used to non-technicians.

No, the APL comes separately in each half. It would be different in a two-family house, but that's not what this is about. Behind it comes the TAE socket as it has been for decades, and the DSL modem (separate or integrated in the router) can then be plugged in there.

With fiber optic, it looks the same up to the APL, only that it is called ONT there. The TAE socket then naturally does not apply.

If APs with PoE are mentioned here, this should also be considered for the utility room. Either a suitable switch with PoE must be installed, or a corresponding number of injectors with power supply are required.

My experience: The builder hotlines have plans up to the TAE/up to the ONT, beyond that it gets very, very thin.

Edit: Previously, it might have been different with the APL in the duplex house, but back then there were also double connections, partly even for neighboring houses on different sides of the street.

No, the APL already comes separately in each half. In a two-family house it would be different, but that is not being discussed here. [...] Edit: It may have been different with the APL in the duplex in the past, but back then there were also double connections, sometimes even for neighboring houses on different sides of the street.

I know ApL – but, as said, that only applies to the copper world which is phasing out – until the end, row and semi-detached houses were served only once. But in the fiber optic era, different regulatory times are already beginning.

My experience: The builders’ hotlines have plans up to the TAE/up to the ONT, beyond that it gets very, very thin.

That is also okay, since the builders’ hotlines do not have the task of planning consultation in regard to the electrician’s assignment, but only on the network level that has its interface from line technology to the house network at the respective APL / HÜP / ONT. That means their task is not comprehensive advice for the customer as builder, but advice for the builder as client of the house connection.