Dell Inspiron 15: Windows installation and partitioning help?

I recently acquired a laptop from Germany that came with Windows 10 pre-installed, but the system language is set entirely to German. It’s quite a struggle since I don't understand the language at all. Even when I attempt to switch the display settings over to English, the OS remains in this awkward state where half the interface is in English and the other half stays stubbornly in German.
The machine was delivered to me without any existing partitions, and I ran into a significant hurdle when I attempted a fresh installation of Windows 7. For some reason, the installer doesn't provide any options for formatting or partitioning the drive; the only choice presented is to proceed with a new installation. When I follow that prompt, it seems to perform a superficial installation, but once the system restarts, everything reverts exactly to its previous state as if nothing happened.

Has anyone here encountered a similar predicament? Does anyone happen to know how one might resolve such an issue?

I have attempted to search for answers on Google, but I haven't been able to find anything particularly useful or relevant to my specific situation.

thx...

I think you might be getting a little mixed up about getting it without partitions—technically, the partition is where Windows 10 lives (and if that second partition isn't there, you'll have to set it up yourself). Anyway, if your goal is to get Windows 7 running, you'll need to boot from a DVD or a USB drive, format the hard drive, and then go ahead with a fresh installation of Windows 7. Do you know what "booting" actually entails?

I understand the point you're trying to make, but I find myself unable to even reach the formatting stage. The system hangs right during the Windows installation process—which has now become a secondary issue I'll have to tackle by attempting different Windows versions.
Before this freezing started happening, I was able to simply bypass the formatting step without any trouble.

I'm honestly not sure if you've run into this yet, but I just wanted to give you a heads-up just in case it hits you too.
Whether you're rocking an Intel or an AMD setup, I've heard that the newer processors are starting to drop support for those older operating systems, because apparently Microsoft is pushing hard to move away from Windows 7 and 8.

There’s been a lot of talk about how the newer Kaby Lake architectures from Intel and the Zen ones from AMD just won't play nice with them, so you might want to skip the Windows 7 install and just stick with Windows 10 to be safe?

You should definitely double-check on the Dell website first to make sure your specific laptop actually has all the drivers you'll need.

much appreciated

Or you could just wipe the hard drive, do a fresh install of Windows 10, and call it a day. That usually does the trick.

Just download Windows 10, boot from your installation media, and you can repartition the drive however you want.