Floor plan of a single-family house on 450 sqm of land

Since you don't know what matters, better show the plan. No link.

May I upload the plan as an attachment?

The plan with the building window and the surroundings. One wonders here why everything is pushed forward, as if the plague had broken out in the east, or there was a nuclear power plant or a landfill.

It’s not quite that bad. The idea was to have only the terrace in the west and the rest of the garden connected in the east. There should (hopefully) also be enough space there for trees, a climbing frame, sandbox, and so on. The inspiration comes from the video "Massive house for small plots (Wohnwerke)" – found on the most popular streaming platform.

Solid house for small plots (Wohnwerke)

I took a look at that. The house stands on a very small urban plot of no more than 15 meters oriented south-north. In Baden-Württemberg, a clearance distance of 2.50 meters is allowed. In addition, the plot is surrounded by apartment buildings. They have made the best of it.
Your plot does not need that at all. With this positioning, you are taking away a lot of quality from your house and your living comfort.
In the dark season, it stays relatively dark inside the house because the south side on the ground floor has hardly any windows. Also, one usually wants to look into the garden or see the terrace as an extension of the living area in good weather and watch the children from the terrace.
In my opinion, the house is wrongly positioned because of the transverse orientation.
If you orient it according to the plot, then a 9-meter-wide house can catch sunlight on the south side, and the terrace can be located there, possibly in a corner position on the west and/or east.
I consider your idea "blocked" and your thoughts misguided if you compare your plot with that of Wohnwerke. Often, the plots are planned 20 meters wide so that 30 meters correspond to 600 sqm. Therefore, 18 meters wide is not necessarily narrow.

May I upload the plan as an attachment?

You can do that. But it’s better if you write here the name of the development area / construction site. Then we will find it. A statement about which property it concerns is then helpful.

Thank you for the development plan. Have you checked in the parking space regulations whether a carport is allowed directly on the street?

Thanks for the development plan. Did you check the parking space regulations to see if a carport is allowed directly adjacent to the street?

According to the parking space regulations, an open carport (without side cladding) directly adjacent to the street is not a problem. Otherwise, 5 meters in front of the garage are required. However, here in town there are several clad carports or garages directly on the street. I would then try in the next step to find out what the conditions for that would be.