Hard drive capacity

Check the system specifications:  support.dell.com, enter service tag.

I did check them. No answers.

Your questions and answers are very, very vague.  What model system is this (Inspiron 3593, 3501, etc.)?  And under Windows, look in the device manager at the storage entry or entries.  You may have a small NVMe SSD for the OS, and a larger hard drive for  storage, particularly with low-end models.

@ejn63 ​ Gotcha. The forum made it seem as if that was automatically there. I have an Inspiron 15 3535.

I was able to locate a "storage controllers" tab in Device manager, and opening the tab there are two dropdowns, one is "Microsoft Storage Spaces Controller", the other is "Standard NVM Express Controller"
There is also a "Disk Drives" tab, which shows my hard drive, it is named "KINGSTON SNV2S1000G" (which seems like a good sign, that IS 1TB correct?)
Also, if it helps, this is the heading / advertisement for this laptop -

"Dell 2023 Newest Inspiron 15 3525 Laptop, 15.6" FHD Display, AMD Ryzen 5 5500U Processor up to 4GHz, 16GB RAM, 1TB SSD, AMD Radeon Graphics, Wi-Fi, Bluetooth, Windows 11 Home"

Thanks for helping.

Look for the drive, not the controller.  It is very possible there's a 100G partition on the drive for the Dell recovery utility, but the rest of the drive (or most of it) should be your C: drive.

Go to the "this PC" and look for your C: drive -- what size is showing?

@ejn63 ​ Where would I find that? I used the search bar and all that came up was "reset this pc". I know there used to be an icon on the desktop but it seems Windows 11 does not have...

Maybe this?

Type in This PC in the search box.  It will open Explorer.

Yeah it doesn't though. As I mentioned it only comes up to reset my pc  :(

Maybe this?

Someone altered that drive after the system shipped -- the drive would not be named Skynet2 on a Dell Windows installation from the factory.

That is a 1T SSD -- why it's partitioned with only a 100G C: drive is a question whoever sold or configured the system will have to answer.

@ejn63 ​ I named it Skynet lol. So once it's partitioned to 100gb it can't be reversed?

It can be, but it may ultimately require a complete reinstall of Windows.

You can open the disc manager (start-run-diskmgmt.msc) to see whether the rest of the drive is unpartitioned, but it's entirely odd the system would have been partitioned from Dell (or was this a refurbished system, where a prior owner may have done that)?

It's brand new, or at least was advertised as such from Amazon. And again, the Skynet thing I just right-clicked the C: drive in file manager and changed the name. I like to know what's what on my home network ;)