Prefabricated garage: earth-covered and walkable

Hello,
we are building our single-family house on a south-facing slope. We have about 1.5 ha of land to manage, mostly commercially (tourism).
Therefore, I will get a small tractor that mows in summer and can be equipped with an excavator bucket. In winter, the vehicle will be used as a snow blower.
I want the tractor to be protected from the weather, which is why I am considering having a prefabricated garage built as a double garage into the slope, where the tractor and tools will be stored.
The garage would be completely covered with earth on the west side, from the back, and from above. The garage is placed on the property so that we would step out onto the garden from the balcony and basically directly onto the lawn above the garage.
Does this work in the forum's opinion? Who has experience?
Best regards

Just so we don’t have a false impression: should the tractor be imagined in the size of a quad / ride-on lawn mower, so clearly still suitable for car garage sizes?

So when I look at my neighbors' prefabricated garages and compare that to my L-stones having to actually hold back the load, I wonder how that's supposed to work? I think you have to (or it is advised to) even update the roof at Zapf if you are in a snow region and that's only a few kilos of water. Funny idea

We also wanted to fill in next to the neighbor's [Fertiggarage] ... but we were not allowed, max 20cm otherwise, according to the structural engineer, it won't hold anymore.

Everything works, but I don’t believe this is possible with a prefab garage. For this, I would recommend WU concrete double walls and a WU concrete ceiling. However, it will be considerably more expensive than a prefab garage. It’s best to find a manufacturer of concrete double walls near you and inquire there!

I also think that it won't work with the common material thicknesses of a prefabricated garage. It will have to be built massively with appropriate structural engineering and a thick reinforced concrete ceiling. 30,000€ and up.