Memory, Gaming, & Linux

I don't do a lot on my computer anymore and on the odd change that actually play a game on it it's usually and older game so there's not problem. However there is one part of the game Dieing Light that I can't play because the game becomes too choppy, I quit playing it years ago for that reason but it's one game I was hoping to finish. I do sometimes play Ark, it plays fine for the post part but it takes a long while to load the map. I don't do near as much with computers as I use to and I haven't really touched hardware or built a computer in years so I no longer even know what most of the numbers and letters for the specs even mean, and I'm looking for cheap simple solution to speeding this thing up. Here's a small rundown of my hardware, can I increas the memory and if I can what kind of memory do I need to buy? I'm sure they'll have to dig it out of a junk yard.

me@mint-desktop ~ $ inxi
CPU~Quad core AMD A10-6700 APU with Radeon HD Graphics (-MCP-) speed/max~1800/3700 MHz Kernel~4.10.0-38-generic x86_64 Up~0 min Mem~957.8/7926.5MB HDD~2240.5GB(21.3% used) Procs~237 Client~Shell inxi~2.2.35