Determine the consumption of air-to-water heat pump from the total electricity consumption

You probably have to start with "Adam and Eve" here...

So we're talking about 2021 and not 2020. (The house has only existed for 1.5 years).

A 7 kW heat pump is also known by now.
It would be helpful to have the mentioned heat quantities and all meaningful meter readings. Each with the correct units.

Information about the house (150 sqm...300 sqm, KfW thing, with/without heated basement, number/age of occupants, location, room temperature(s), etc.) would also be good for "estimating the consumption".
The heat pump certainly also has one or more meters integrated.

With an annual demand of 6800 kWh, I would guess 4000 kWh for the heat pump and 2800 kWh for the household.
But let's wait for the further numbers...

We are talking about 2021. However, I can only provide the data for electricity for 2021. I did not record any other meters last year. Therefore, the other readings are practically from 1.5 years.
Our single-family house is 150 sqm, the entire insulation is at KFW40 level, no basement, 2 occupants each around 30 years old, location Lower Saxony and temperatures each 20 degrees, bathroom warmer, bedroom colder.

Tomorrow I will look for the heat pump manual and then check the reading. Without the manual, I have only found the above-mentioned readings.

Then the other readings.

Separate meter distribution box: 1,294.59 kWh
Heat quantity meter: 12,082 MVh
Heat quantity meter: 2,477 MVh this should be the one that is in the hot water circuit.
Electricity consumption 2021: approx. 6800 kWh

Almost 7000kWh for a 150m² KFW40 house sounds like a lot, but it could also include an electric car, sauna, mining farm, and so on.

What kind of unit is MVh?

I strongly suspect that the second meter is for the photovoltaic system!? The meter reading could be the feed-in?

The system will have an emergency switch, right? You could insert a Shelly PM there, which would then provide you with the consumption data. Especially with photovoltaic systems, such Shellys are not a bad idea, because you can then analyze quite well when, where, and how much electricity is generated….

Almost 7000kWh for a 150m² KFW40 house sounds very high, but it could also include an electric car, sauna, mining farm, and so on.

What unit is MVh?

For a grass plantation in the basement, the electricity consumption is too low again….

The Mvh will be kwh. For 1.5 years, that amounts to roughly 8000 kwh of heat energy that the house consumes. That fits quite well with 150 sqm and KfW40 in my opinion. Assuming 2500-3000 kwh of household electricity, you get an annual performance factor of about 2. That would be very, very poor, but can already be plausible due to the long and cold winter and the hot water consumption. So I would now use the time to optimize hot water preparation and heat pump settings. Of course, these are all just assumptions.

The Mvh will be kwh. For 1.5 years, that's roughly 8000 kwh of heat energy that the house consumes. That fits quite well with 150 sqm and KfW40 in my opinion. Assuming 2500-3000 kwh household electricity, you end up with an annual performance factor of about 2. That would be very, very poor, but could be due to the long and cold winter and hot water consumption. So I would now use the time to optimize the hot water preparation and the heat pump settings.

Of course, these are all just assumptions

With the "fridge temperatures" (20 degrees) in the KfW40 house, I would have now guessed a maximum of 2000 kWh for the heat pump.
But where are the remaining 4800 kWh "wasted"?
Or is it just normal household electricity demand and totally botched hydraulics/floor heating?
Hot water temperature possibly at 55…60 degrees?

@TE: Your consumption remains a mystery.
We need more input.

I recommend recording all meter readings - with the correct units - daily from now on until all crystal balls here are polished.