Got a PC ... What would u upgrade?

A friend of mine was upgrading his business' PCs and the old ones were being decommissioned. He gave me this for free. It was used mostly for working in CAD and GIS. Knowing I game a bit he thought I might get some use out of it.

I've it plugged into a TV at the moment that I believe handles 1440p resolution at 60Hz using display port to HDMI

I play mostly old games so I know it can handle those. I downloaded gamepass for PC and got Halo infinite up and running but I think all the options are set at low graphically speaking. It runs pretty good all in all

So the question really is what if anything would y'all upgrade ?

Hoping I can get away with what I have for Indiana Jones