Newb growing from seed

Ok this is my first thread and my first grow. I am planting from seed because i don't know where to get clone from. Also my friend insist that his seed he gave me is female which i doubt, though he did gave me more then one. So i germinated one seed for 3 days and i planted it in a cup with soil. I only did 1 seed because i have extremely small space to plant them, so i can only do 1 at a time. After about 3 more days i can see it sprouted up. Now i know vaguly from skimming through the threads that you are suppose to wait like a week or two? before transporting them but i had complications. If they die i will learn from it. I build my own hydroponic system and transported it in there which is in my closet. I have a 3x24w T5HO lighting. I do not know what strains of seed they are. I do not want my weed to grow tall so how do i do that. I skim through threads but couldn't seem to find it. I did see about film and topping but still do not have enough info about it to do it. When do i do topping or filming to stun the growth, also how small can i make it and which is better film or topping. Lasty how do you even go about film or topping.

Hi,
im on my first ever grow too.
Mine is about 9 weeks old and tbh i just put in a big pot with a mix of grow bag and perlite.
Has a 250 sodium light kept 2 feet above the top on a 12/12 in a converted cupboard 2 fans blowing in and 2 out.
I topped mine when it reached 5 feet, all to do is go down to the main set of branches growing directly under the main bud @ the top then about 1 inch above it cut it off.
That was a week ago and its has 2 main tops on it now and over 120 bud sites.
Mine is swazi and this was the 1st seed i did and its ok, no expensive nutes either just plain ol organic tomato plant food when it started to show preflowers.
Check the faq it helps a lot .

If u dont want it to grow too big 12/12 it , hopefuly in your case you have indicia type strain they are short and bushy

dude look into low stress training thi will solve your problem of hight the best way in my opinion