As far as i know, communism from an origin and tought as it on the theoretical plane has TWO Big problems and those are:

1. Comunism tends to not know what actually is needed to produce

in a capital-less society, being, on this ideal no money, nobody can't really say what its needed, when, and how, hey maybe democracy can do a rough equivalent to that BUT not as good,decentralized and acurate as money itself.

2. Comunism has a problem on incentives

Incentives, can be divided into by benefit,you can get something by doing other stuff, or you do that other stuff in hopes of avoiding a not so agradable scenario.

The thing is that communism, being a stateless, and buisnessless society on its end goal, only has to incentives, happy chemicals for doing something, its a matter that fullfils you or you directly need or social pressure, either good or bad, there is no other ,mostly, third way.

So I want to know wether how could it work in a modern,globalized society and how those two problems can be solved or not and on the how of the posible solution.

Btw, I want to know if im being rude or something,and my english is not that good but im genuinelly curious about how the left can solve these problems.