@Hrrng327 The £630 laptop I linked has most of the same specs as the one you were considering. The main difference is that it doesn't have a fast solid state drive, only a slow mechanical drive. All of your apps would still run just fine, only they'd load more slowly, and the same goes for Windows. It's not a big deal, more like an inconvenience.
You could upgrade in theory, as in, you could add an SSD to the laptop. But in practice, that might be more work than you want to do. At the very least, you'd need to physically install the new drive and reinstall Windows onto it to get the benefits. And if the laptop only has one slot for a hard drive, you'd need to remove the existing one first, and so you'd need to have a way to transfer your data from the old drive to the new one. This isn't difficult by any means, but it is work, and you'd also need to redownload any apps (like Sims 4) you wanted to install.
If you really like the laptop that's out of stock, this one has the same specs, including the small fast SSD, and it's also £700:
https://www.argos.co.uk/product/3039061