HELP! First Time Grower w/ Questions (& Statements)

[Kundun]

Statements
- first time growing a cannabis plant (grew from a seed that sprouted Nov 25, 2023)
- I read that some pros top their plants 5 times, so I did when the plant was about 45 days old
- I had fungus gnats that I got rid of with Neem Oil Spray and Diatomaceous Earth
- thinking the shift from 24 hrs light to 12 hrs light was done at a certain age, I started reducing the light by one hour more a day to get to 12 hrs on 12 off
- I added 15 ml Humboldt Secret liquid plant food to one gallon of distilled water and began using it
- after watching a pruning video, I realized that topping my plant 5 times means that she needs an extended vegetative stage, so I thinned the bottom half of the plant (02.05.24) and went back to 24 hrs light
- the plant seems to be thriving (Photos attached) but there is some slight yellowing and a lot of brown tips

Questions
How often should I prune and thin the bottom half of the plant?
How will I know when she's ready to go to 12 hrs on, 12 off?
The Humboldt Secret says to use during flowering, should I stop using it while in Veg stage?
The gnats are gone and I heard Neem Oil can give your buds a funny taste so I stopped using it but plan to continue using the Diatomaceous Earth for the nutrients; the very tips of my plant are brown and I read that that means the plant is receiving as much nutrients as it can handle; should i stop using the Diatomaceous Earth for now and if so, when should I start using it again?

Your time, knowledge and experience is appreciated.

 

[Newty]

I like running my lights in veg at 18 on 6 off. Others use different schedules, this is mine.
12/12 is going to start your flower cycle, your are around 14 weeks of veg now so I would say you're close.
Your plant can double or triple in height in flower so you need to time your flip also with the height of your plant, you don't want to run out of height and your plant end up to close to the light.

 

[jdog22]

hey man a little tip, make some small holes in your fabric pot and tie some of those longer branches down to make a wider canope and have more space to grow upwards :)