Let's take a serious look at what you can do... PART 1

 So we all know something isn't right.  If you do just a little research you can learn that critical minerals and energy depletion are obvious outcomes of consumption at a high rate by a large population on a planet with finite resources.  You can also read about warnings from the early 1900's, the 1950's and the many simulations done in the 1970's that all tried to make society aware that there are hard limits to growth - often messaged in proxy statements designed to destroy demand (a whole range of nudges from birth control to fleet fuel consumption guidelines and just let your mind wander - there were many more).  

So how can you start to model your environment and see what might be possible with a small grouping of people and nothing more than land, water, sunlight. reasonable soil quality and healthy biodiversity. Let's consider these natural resource inputs to our open source model.

What about human inputs? Well, labor from healthy individuals is needed, knowledge of agriculture, how to administer medical treatment, how to go about food preservation and storage, and some mechanical ability (build and repair stuff)

Next, the system model will need a starting sink of cash and materials to enable agricultural inputs like a stock of heirloom seeds, and/or some livestock and buffer stocks of feed, a starting assortment of farming tools and modest equipment (this is not a large operation but a sustaining village).  Another input would be soil amendments like manure and compost, lastly some quantity of water from a well or stream for irrigation and storage.

People need to live somewhere so infrastructure has inputs to the system model too. Housing of some kind in needed, energy sources like wind, hydro, wood, peat etc., storage buildings for grain, root cellars for cool storage or over winter keeping, maybe refrigeration if energy is not a pressure point. A way to get around, maybe by bikes, golf carts, or horses. Lastly waste needs to be managed properly and thoughtfully.

Another input must be a decided way to exchange stuff.  Barter, or work to a schedule of time for each person then share etc.  This is where a valued material like silver might come in.  

Going deeper wherever you live you have climatic realities that encourage seasonal planting and crops that grow well, perhaps your crops could be exchanged with the community 50 or 100 miles away that grow other things...  You will also need to know how to mill grain, ferment, can, dry or smoke various products for storage so those are subjects somebody in the community needs to document, understand and lead in teaching. 

The model probably needs some external inputs too. Stuff like replacing worn out metal tools, replacement parts, replenishment of medicines, and perhaps a religious leader.

Constraints would be your climate growing season with all of its components like growing season length, amount of rain, days of sun, energy availability, storage capacity for harvested crops, available land acreage and some population set-point of this village.

That should be enough to get your brains started!  Next we'll have a look at some reality checks on caloric intake and other benchmarks needed to meet to be successful.