The hard drive may be 256gb but a big chunk of that is taken up by Windows and also there will be a hidden recovery partition. So 170gb sounds about right. You can’t reduce how much space windows takes, and the recovery partition is worth keeping in case you get in to trouble.

There may be programs HP have installed that you can remove in add/remove software to make a bit more space. HP is notorious for bliatware - installing things to try and sell you stuff. Probably a good few gb may be that crap.

If you download a big game, then it’s not a big deal if you’re using that game. 80gb is still plenty. And you can delete the game when you’re done and use that 90gb for something else.

256gb isn’t much but it’s enough unless you want multiple big games installed or have a big library of data such as movies or pictures.

Also it may be possible to upgrade the hard drive - depends on the model and how accessible the hard drive is. If you can access the hard drive to replace it then you could get a 1tb drive for example. There are guides online but basically you’d need to copy the existing drive to the new drive (would need a USB adaptor to mount the new drive first) and then swap the drives round. It very much depends on the laptop though.

Another option is an external hard drive connected via USB - it’s not good for gaming or running big programmes but it is fine for storing movies and pictures.

If the priority is to have multiple different big games installed at the same time, then upgrade the hard drive. Most HP models it’s generally doable without much fuss. More difficult with the ultra slim devices though. Search for your model online and see what people have done.