seed need light?

i just read the post below mine about how u don't need. or should use light before the seed has came past the soil? but if my plant is in a closet, how can it grow without light? i mean i understand it needs heat, but is it just heat? wondering, very confused.
-ty

also another question, would u say from first day (already germinated) should i do 18/6? or 24? or what u guys say for the first week or two?

seeds need no light to spruce, that is a fact. if you want to increase your chances that they spruce or/and spruce faster, use a cloning agent/hormone.
(i do so and all my seeds spruce within 48h, every single one!)

go for 18/6 and not for 24. 18/6 gives your plants a rest to grow in, especially roots grow then. 24/0 adds only to your power bill.