If your willing to pay a great game would Oxegen not Included, it is a single player game and doesn't require to much from your specs.
If you like any vehicle combat games,you might like War thunder, it is mainly multiplayer though, aside from the few dianamic campaings you can play, the game is F2P so you don't need to worry about spending a penny on it.
I also heard somewhat about Stardew Valley, I can't say for myself but its there if you like pixel games.