Possible Strain ID opinions/suggestions, first plant (was gifted it)

Greetings and salutations. I have a few major inquiries, and would like some assistance with experts. I was graciously gifted this gal, Alice, two days ago. She is two months old. I REALLY wish for her to survive, so I am looking to receive a few quality answers.

Firstly:

- Recently acquired, total newbie for sure, 2 months old, in a 7 gal pot. Non-MG soil. The leaves are deep-light green, but definitely green at that. I have been using natural sunlight, which I already know it will certainly need more than just natural sunlight, She is fed with nutrients, I will provide what kind, but I do not have that information atm, it has nirtogen and magnesium in it which I had mixed a tablespoon per quart of water. I am not sure if every plant does this, but she has alternating branches, meaning they criss-cross going up the plant, with four branches stemming from the same point for each portion of the stem.

Okay, may I ask:

- Would anyone happen to know, by either picture, what this strain is or is similar to?
- In a 7-gallon, would a half-gallon of water/nutes in 2.5 days be considered over-watering?
- She is a bit droopy of late, could it be due to over-watering, (under-watering?), not enough light, or a combination?
- Do I even need fertilizer? Could I use only 6.5 pH water and she will still thrive and grow further?
- Other than watering, feeding, regulating light/ventilation, examining, and occasional pruning, what more do I need to do to ensure she will live well and thrive a long while?
- Music helps, correct?

That is all. Thank you for your time, I appreciate it, and I promise she will too!

First of all do some research.

You cant tell a strain by the look of it.
Water when the top 2 inches of soil is dry. (if its not dry dont apply)
If that^ isnt how youre watering then that could be the problem but also what type of light source do you have?
Nutrients arent absolutely required but if she has deficiencies then she needs something
Keep light on her, give her water when she wants it, keep it the right temps, DONT CUT IT UNLESS YOU KNOW WHAT YOURE DOING.
Dont bother with music, if you truely care, give it good vibes when you tend to her.

And remember, DO SOME RESEARCH.

you most likely will never know the strain of it until the very last bit and even than its still a guessing game.

I heard playing Mozart on repeat will increase yields by 30%. edit: I shouldn't really say that around here, someone might believe me.

"Obviously Girl Scout Cookies.. Duh!" jk