I'm not entirely sure what you're asking with communications and flames, so I'll just give a simple answer. Communications, is most commonly used in the workplace as the official term for data transmission, for example "satellite communications," in most other contexts "communication" is fine. Flames is more simple. One flame is a small amount of fire, for example, a candle has a "flame" and many of those small bits of fire, are "flames." So a house could "burst into flames" or you could "blow out the flame of a candle". Imagine that, in fire, where each part of the fire [emoji] creates a point, that's one "flame". Computers are brought into common people's homes. "Brought into" and "brought in" are the same, it's just that English speakers often drop the "to" in "into." The former is actually the correct grammar for this example, but native speakers don't really abide by correct grammar rules. ("brought in" would be used when the destination was not explicitly said in the sentence, eg "computers are brought into the house" vs "computers are brought in"). "Brought to" says that the computers are moved to the house, but it doesn't explicitly imply that they are actually inside the house. That doesn't mean that it excludes the possibility, merely that the focus is not on the computers being in the house in the end, but on the computers moving from somewhere to the house. For example, if you say "I'm going to my mum's house" the focus is on the fact that I am going to travel to my mum's house, with the implication that I will go inside when I arrive, but if I said "I'm going into my mum's house" the focus shifts to the fact that I am currently not inside, and will be moving inside the house. So, "into" is the correct word for this context. Final point, if you want to add "be" it would be "are to be brought into" or "are going to be brought into" these all depend on the meaning you want, which I don't know.

With physical countable things like a flame, you have one flame, two flames, etc. There is no complication. Communication is countable when it means message eg I sent three communications yesterday. But it is uncountable when referring to the process or activity in general e.g. Communication between my neighbours and me is sometimes difficult. The issue is to understand the meaning of the noun well and know if it is countable or uncountable. Bring something to or into a place. There is motion so we need "to". If the motion also includes entering an enclosed space like a house, then"into".