Floor plan change - Load-bearing walls in the apartment. What to do?

There were a few more questions ;)

That will follow anyway. First of all, the question for me is whether I should take over the apartment or if nothing can be made out of it.

There is a world of difference between renovation and refurbishment. A refurbishment can also cost six figures. A renovation can only cost 1000€.

We can say very little based on a floor plan and the statement "I still need an office."
Is it an old building, well or poorly maintained, or new?
Is it moldy, is there water somewhere, and is it one of 10 apartments or in a two-family house?

So the question cannot be answered without mentioning any facts and parameters. Also not without knowing a bit more, such as the budget.

With the question of whether to buy or "take over" a house or apartment, you should take a few weeks to ponder and note the pros and cons. There are also other factors, such as personal life situation or the location of the property.
And then you go to an expert who should check everything.
Usually, structural engineers are also experts and can assist you with new planning.

It is also pointless now to question every piece of info behind it.

Basically: you can make something out of everything. It is only a question of cost.

It is the basement apartment in a three-family house owned by my parents, which is only inhabited by the family itself. The year of construction is unknown. The house was renovated in 1985 and 2000. The apartment was inhabited until two years ago - no mold, no water damage, and partially has a basement. Since then, the apartment has only been used as storage space. Theoretically, one could move in if one is okay with the outdated furnishings. The windows can be kept. The electric screed is brittle and must be renewed/repaired, as well as the floors and walls accordingly. However, the parquet flooring in the bedroom and living room is still in good condition. Additionally, the bathroom and kitchen are no longer visually up to date. The costs should, of course, be kept as low as possible. However, I currently have no idea of the costs at all, as I have never renovated before. The question is whether it makes sense to use the apartment as such again and at what point it balances out with my current rental costs.

So I think, to turn it into an apartment that meets our current standards, you will have to take quite a bit into your own hands. Bathroom and pantry are in the most unfavorable locations possible. The suggestion has already been made here: to make a modern bathroom out of the toilet, pantry, and the hallway in front of it. Turn the office into a bedroom. However, I seem to recall that the street runs past there. Then of course the question is how busy that street is...

Load-bearing walls can certainly be replaced by supports and beams, but that is already a bigger operation—and costs accordingly.

The fundamental question is: do you want to live there long-term? For example, if it is in a trendy district and the possibility exists to rent out the newly renovated apartment well if it no longer suits you, then an extensive renovation/refurbishment makes more sense. Or is it in the middle of nowhere and your family lives there and it would not be welcomed if this apartment were to be rented out to strangers? Then I would seriously consider whether the apartment, even rebuilt, will meet your standards in the long term.

For a nice old building in a good location, I would say: go for it!

But here we really know far too little about your circumstances (future planning, budget, circumstances of the "family house," etc.).

Of course something can be made of it, lines can be rerouted, everything is possible and merely a question of money.
Only: what use is a fancy design if the whole thing may cost a maximum of €100,000?

Budget up to 100,000 €. The location is good. The apartment is in a quiet district. 1 km to the nearest large shopping facility. The street is not very busy. So a bedroom facing the front is certainly conceivable. Renting out is possible if I no longer want to live in the apartment myself at some point. I was mainly looking for tips and suggestions on how the design could look.

I can't even see where the entrance is. Is there a staircase where the recesses are? Why are there two? Elevator? Where is the street, where is the garden? Far too little information.