Techs and Progress
The game progresses through the accumulation of technology points you gain by expanding your population, gathering raw materials and crafting tools and by building structures. Through the eras more points are needed to gain technologies or enter a new era which offers new techs.
Almost every first item and its greater number (5, 10, 100, 250, 500, 1000) of anything produced, crafted, built, killed and butchered offers +1 tech points.
Surviving the winter adds another +1 points every full year, and after surviving the first 2 winters you get an additional +2, not to mention you ticked off a Milestone.
Reaching Milestones by accumulated knowledge, expansion of your settlement, having erected menhirs or entering new eras adds +2 tech points, and the arrival of babies and immigrants at the interval of 5 offers +3.
There are 6 eras to progress through, after which you can start producing steel.
Theoretically, you can reach that era directly after gaining ‘just’ 139 points.
Once a tech has been chosen, it is irreversible (unless you open your last auto or quicksaved game). Hold off on techs to save up points to move up eras more quickly, as the unlocking tech to that era comes available. Most eras can only be entered by gaining a certain preceding tech by only which you can unlock the new era. Which tech to go forward with is completely arbitrary and up to you. At certain points in time you will find yourself wanting for a certain tech you wish you had taken earlier instead.
There are a few directions you can take; either go for a well-fed and expanding population, or producing weaponry and depend more on trade, or set your people to the fair but heavy task of raising menhirs, henges and dolmens and gain a lot of prestige.