Hmm, well, a good first start is how you want the game to progress. You have the goal, but how do players get there? I'd suggest a simple turn system that breaks down into a roll for Inventions, then a roll for War. Inventions gives players a chance to move up a peg on the progress towards upping their society a tech tier. War lets them screw other players over and potentially steal their invention. After everyone's civ finishes their turns, each player rolls against a DC adding their invention bonuses to see if they move up a tech age. Once one person moves up, the others have an easier time advancing to not snowball, but it gets harder to progress the ages as it goes. You'd just need to play around with how war and everything shakes out, numbers wise.
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Since, ultimately, the game's about the absurdist dream of cooking food in a microwave, I think hunger should be a core mechanic. "People died to scramble this egg!" Maybe make it a token thing, I know this concept is slowing becoming more board game than TTRPG, but maybe you have to forego science and invention for the practicality of keeping your people fed, or opting to feed helps your population which helps with war, or you treat it as your civ's "health" as an alternate lose state for more pacifist games