Mark said:

Since numerous generations of people lived before you and me and
apparently have survived (You and me are living proof of that), and
these people did not have luxury of Internet, public libraries,
universities, even high schoolsd, still they did know how to get (or
make ) food for their plants? Correct?

Sometimes what people did in the past is to wear out their soil and move
on. But the cleaverest farmers knew how to use manure (animal and
human) to return nutrients to the soil, and to rotate crops from heaviest
feeders, to lighter feeders, to fallow.

So, is this the where the compost comes in?

Compost has sometimes been described as 'artificial manure' and
intentionally making composts, IIRC, is a relatively modern thing.

Can I take the mulch I bring from dump and make compost from it? Fast?

If you add plenty of nitrogen (urea is possibly the cheapest source of rapidly
available nitrogen). And some fresh manure would help supply
microorganisms.

For *fast* you'd need to mix it well to start off and be sure to provide for
constant air-flow through the compost; build it on a raised platform and/or
run perforated pipe through the pile to supply air-flow.

The more varied the inputs to the compost, the more likely you are to
have compost with a good 'nutritional' value for the plants. Coffeegrounds
can sometimes be had for the asking (Starbucks has a national program
to encourage composting). Maybe you could get spoiled hay locally,
vegetable waste from a market (corn shucks, for example), seaweed (if
collecting it is allow), or manure from a stable.
--
Pat in Plymouth MI ('someplace.net' is comcast)

Any technology distinguishable from magic is insufficiently advanced.
(attributed to Don Marti)