Forgive the nature of my visual support materials

I've had a couple of Goyomatsu for a week or so. I've been doing something kind of 'indecent' with them (hence the lack of photograph to avoid flamers) but I have a question about one of them, which I fear may be misplacing vigour. I would like to state here that I deem this post to be about pruning, as all of my questions are asked with an aim towards understanding the best time/way to prune my bonsai, but there is a fair chunk of background info that I hope won't be interpreted as being off-topic!

As you can see in the sketch attached (the circled portion) there is a small node sprouting from the trunk of the pine which has grown some needles and even a small, er, I'm not sure if one would call it a candle or a bud, just a little mace of lush looking needletips. I am unsure what I wish to do with this node, I feel that a small branch at this point may look picturesque in future (i may even try to make it appear to be 'Jin') but I am unsure if it is sapping vigour from nodes and branches further along the bonsai, and perhaps preventing a larger thickening of the trunk...

I am rather hoping someone would be able to simply list off the various things I could do, and the various consequences thereof, with this little branch.

To provide a bit more background, I am enthusiastic about bonsai but I've a limited ability to inquire after them at local dealers (I live in Japan) and youtube videos rarely seem to touch on the age and precise species of my bonsai (plural) As such I've a variety of only partially understood directives floating around my head.

Specifically I'm unclear on the following things:
> Needles. Can trimming/halving needles in spring redirect vigour?
> Buds. Would cutting off buds at this point in the year have any positive or non-harmful effects? Such as on redirecting vigour? Or is it entirely the wrong time to do it?
> Age. The bonsai is only a few years old, I would say the trunk shown in the sketch could be measured at about 4-5mm thick, the total length of the bonsai (now bent into the attached shape) may be around 10cm including new growth) Is it wise to be doing anything to these bonsai this year?
> Watering. I am currently in spring, but my city is famous for being the hottest in Japan in summer, and spring is already pretty steamy on sunny days. At the moment I am moistening the soil with a spray whenever I notice that it has dried out (I've been doing this by sight, not by touch test) which is about once per day. Is this too much?
> Fertilizing. I've read and heard a lot about fertilizing on western sites and videos, but I've not had any advice about this from local bonsai enthusiasts with whom I was able to chat. What is fertilizing? What fertilizer would be ideal for my goyomatsu? ('white pine bonsai' i believe)

>> The bonsai was transplanted into a larger pot after being bought at a bonsai festival, the uppermost roots have been exposed since I put them in, it doesn't seem to have affected the vigour of the bonsai to date (since purchase many buds and even a couple of new branches have sprung up)

My default position is to do nothing, but I wish to gather information to securely understand my relationship with this bonsai.

The best thing you can do with this tiny seedling is nothing other than watering. There is nothing to prune or pinch. It will be years before this is big enough to do much