Well you need to have sex with other allies to create more units UwU
Getting started: get 20 wood, 20 stone, learn the build house skill in the skill tree. Build a house ASAP (this increases your population cap by 2), (Q opens build mode) , immediately have sex with your partner, preferably twice to get two new allies. Building more than one house and having more kids is preferable, after having 10 population you're already a force to be reckoned with.