I light a fire.
The fire went out.
I lit the candle.
I doused it with water to put out the fire.
The fire went out because of the wind.
We all warmed ourselves by the bonfire.
I put the pot on the heat to warm it up.
Please make sure the meat is cooked all the way through before eating.
緋 (scarlet) and 火 (fire) are pronounced identically as ひ but are completely unrelated in meaning, distinguished only by kanji and context.
火 is the general word for fire of any kind, while 焚き火 specifically means a controlled fire that someone has built outdoors.
charcoal fire
open-air fire; bonfire; campfire · open fire (in a kitchen)
low heat; low flame; simmering
fireball; ball of fire · will-o'-the-wisp; jack-o'-lantern
dying down; waning; declining
live coals; burning embers · cause; trigger; spark
playing with fire (literal) · playing with fire (figurative); doing something dangerous · playing around (romantically); flirting; having an affair
high heat; high flame
arson; incendiarism
fire extinguishing; putting out a fire · Edo-period fireman
leaping flames; flying sparks · spread of fire (from leaping flames) · spillover; unexpected repercussions; spreading to uninvolved parties · impetigo contagiosa
sparks; flying sparks
medium heat; medium flame
origin of a fire; source of a fire
brazier; hibachi
ceremonial bonfire for sending off spirits during Obon
fuse; pilot light · trigger; spark; cause
burning at the stake; execution by fire
fire pan; brazier · heating; applying heat · first lighting; firing; kindling; igniting · pasteurization
glow of a firefly · nearly extinguished fire; embers
pan cover; touch-hole cover
controlled burn; prescribed fire; field burning · wildfire; bush fire; grass fire
will-o'-the-wisp; ignis fatuus
heat level; fire strength; condition of fire
red imported fire ant
foxfire; will-o'-the-wisp
fire arrow; incendiary arrow · rocket