Preparing the installation for a smart home in a newly built house

Hi. I would like, at the stage of building the house, to immediately envisage a place for smart home systems, which I might do at some point in the future. The problem is that, as of today, I don't know what systems I will want to do one day. I'm green on the subject, and don't know how to approach it? As far as I know, most lighting or roller shutter control modules are mounted in flush-mounted boxes - the question is whether standard size boxes will suffice, or do you need to make some bigger/deeper ones? In terms of wiring, do you need to take on any additional wiring straight away? I guess these days everything works over WiFi? Please give me some advice for the layman .

Familiarise yourself with the pros and cons of the systems - wireless and wired - and decide which you want.
Of the wired ones, see for example Loxone, Ampio, Grenton, KNX. You can also do a lot on control panels - e.g. there is a sample project on the Ropam website.
Wireless is also available in various versions - from cheap Chinese devices working on the basis of their servers, through their own server such as Home Asssitant or Fibaro and solutions such as Exta Zamela, to systems as above expanded with wireless devices.
WiFi is probably the most problematic system - with a larger number of devices there are problems with routers, delays, dependence on external suppliers and server failures. It's better to use Zigbee or Z-wave and your own PBX.
The advantage of wired systems is stability of operation.
Also consider whether you want to do it yourself or outsource it.
What to do next will depend on your choice of system - there is no universal way.
If you want to mount devices in boxes - it's better to have deep or pocketed ones, it will be easier to mount or service. If wired it's better to know which one and lay the appropriate wiring.