ᐅ Stains on freshly oiled hardwood flooring

Poorly done.
Thoroughly clean to remove the oil, sand down properly, and reapply oil. The beginner’s misfortune – especially with this type of maple parquet, which even professionals find challenging...
There is no other solution for this total loss, except to live with it...

Thank you all. I will take a look at the Osmo wax! I will sand more finely...

That alone might not be enough. You change the sander at those spots, and the sanding pattern will be different. That difference will become visible on the oiled floor. Try responding to the follow-up questions...

The floor has dried.
However, it doesn’t look as bad in person as it does in the photos.
The issue was partly that when removing the pad, more oil tended to remain—mostly around the edges.
There are also stains that could be from food, drink, or oil. These have likely soaked into the wood.
I am planning to lightly sand over it and then apply Osmo decorative wax, aiming to lighten it a bit as well.

I don’t think it’s that simple. Osmo is not a cure-all but just another supplier of finishes, although I generally like their products. Applying a different product on top of an existing one doesn’t seem like the best solution to me. Usually, sanding is the main cause of problems later on.

Can you explain how you sanded it or how you plan to do it now? For example, are you using a machine, and will the approach vary depending on the area?

In principle, I would recommend trying it out first on test pieces to see how it works.

If you want to use Osmo, there are various options like hardwax oils, decorative waxes, or stains...

I sanded with a large machine using 100-grit sandpaper.
Then I vacuumed and cleaned.
After that, I applied oil.
For the edges, I used a handheld sander.
Now I want to do the finishing work by hand...