כ־ב־ה is a tight, vivid root: a flame going out. The contrast between its binyanim is the clearest lesson in Hebrew morphology you can ask for. In the pa'al the fire goes out by itself (לִכְבּוֹת); in the pi'el someone actively puts it out (לְכַבּוֹת); the same pi'el extends naturally to turning off a light or a machine. The agent who does this for a living is the firefighter. One root, the full arc from a candle dying on its own to a fire crew on the scene. Every word here is verified against pealim, niqqud included.
The same root runs through the verb system. Each binyan is a voice: it bends the one idea into active, passive, causative or reciprocal. Tap to hear.
This root is a textbook pair: the pa'al לִכְבּוֹת is intransitive (the fire goes out on its own), while the pi'el לְכַבּוֹת is the active, transitive counterpart (someone puts it out). The nif'al לְהִכָּבוֹת is the passive (to be put out), overlapping the pa'al in everyday sense. As a final-ה (ל"ה) root, all three infinitives end in ־וֹת. No hif'il, pu'al, huf'al or hitpa'el are lexicalized here.
Same root letters, different noun moulds (mishkalim). The mould tells you the function: who does it, the act of doing it, or the thing produced.
Strip the prefixes, suffixes and vowels. Three consonants remain, and the meaning lives there.