What buildings should I get first?
Well first things first you would want to get that wood workshop as soon as possible because of all the nice sexy upgrades you can do.
I recommend building
A few Tents as needed to get some workers going.
Then build a Saw Mill cause you are going to need some wood, trust me.
Then Build a Hunter’s Lodge or Fisherman Quarry or both if you can depending on your terrain. That should provide enough food to keep your colony happy for a bit.
After all that you should have enough resources to buy the Wood Workshop
once your wood workshop is done I suggest Researching Cottage first. you can never have enough workers.
With all the building’s your gonna need some power so after the wood workshop invest in a Mill for some Energy.
You don’t have to worry about zombies attacking you till like day 4 and with that the militia that you started with will be enough to fend them off till the horde rush.
whatever side or area the single zombies attack You I suggest building a wood tower there for defense because more then most likely more will come from that same direction.
Research the Great Ballista. With this baby the first two horde rushes will be a breeze U wont even have to build a wall till later with these bad boys defending the threshold.
And there you have it the basic startup for your colonies the rest you can freestyle and see what works for you just keep in eye on your resources and you should be fine Also its great Idea to double up on wall protection later in game.