PREPOSITION IN OR AT "HOME"

[pablo2607]

I know there has been some discussion about the prepositions IN or AT in this forum, but perhaps you all can humour me.
A student posed the following question:
Why can I say I have internet at home and not in home. (which she feels IN HOME is also correct usage).
Whereas, it’s okay to say I have internet in my house and not at my house.
Even though a house is not a home, they are synonymous.
With reference to a house, there was no difficulty explaining the difference, which she understood.
However, to my student, it doesn’t make any sense that she can’t say I have internet in home using the same structural logic and I find impossible to explain.
My request, who can help me explain it.

[The French]

Hello,

I am not a teacher, but generally you use 'at' for precise location, example, 'I am at the corner of the street',or I am at the bank.

Your home is a location, if you believe yes, use 'at', but the other preposition 'in' is more used for space, example, 'My money is in my bag'.

Hope its help you.

Have a nice day (Buenas tardes).

[konungursvia]

In home does exist, for example as an adjectivial phrase: in-home medical care.

But it's rare, some people would find it awkward, at home is far more common and versatile.