I'm really debuting I'm amateur please help

it's not the light and reducing light if it is a hot soil will have opposite of the effect you want. the plant's rate of use of nutrients will reduce but provision rate stays same, so the toxicity gets worse in that context. Yout doil id probably a little too hot for a small plant. if it made it this far it'll survive. May get more damage before the plant is robust enough to handle your soil's nutrient level. also, you are warering wrong.. not an opinion. you do not choose teh volume of water. that is a big red flag of doing it wrong. water until entire pot is wet, no less. Wait for top 1" to dry. Repeat. Don't deviate until you know what you are doing.. even then in soil, don't deviate, lol. the volume will remain the same if you water at same point.. the time between will change. as the platn drinks at a faster rate, you'll have to irrigate more frequently. Transplanting will reset that trend a bit, but it will continue.

If you in soil and it is fortified they should not need anything by water for the first 2 weeks to 2 months depending on the soil and size of pot. I find a ph of aorund 6.4 is great in soil, but it is very easy to over water. Follow your lighting manufactures guide for hang heights. and don't go over 18hr a day of "on" time. 18/6 is the maxium I use then down to 12/12 later. Good Luck!

What PH are you watering at? Usually Seedlings don't require nutrients until they are one and a half to two weeks. I usually just feed them Plain water at a PH of 6.5 (For Soil) for the first 2 weeks. Feeding them Nutes when they are younger than that can cause burning and stunting in my experience. Though 100-200 PPM is Rather Low, it may be causing the burning. Some strains can be more sanative than others. Killed a few seeds that way in the past.

Is the zone around the seedling too hot? When I use organic soil I'll make a hot layer on the bottom of my pot with a layer of mix that's mixed down with an unfortified soil and the zone immediately around the seedling is JUST unfortified soil. Seedlings don't do well in a hot mix.

800 ml is enough for first two weeks . burn is either light ( doubt it ) or wrong ph, very low, plus i guess you overwater with such amounts.