Psi balls are step one of spell casting [you've mastered walking, now try running] while they can be used to create things like thoughtforms, the psi ball can be "pushed" into an object for spells. How you charge a candle [or any item] is to make the psi ball, then cup your hands around the candle and put the energy into the candle while thinking of love, luck, or whatever energy you are charging. [there are other ways to use psi balls, but that's how they're used in a spell-casting setting]
I studied auras a decade ago, so I can't be of much help there, but your aura is a natural energy field around you. It grows and changes colour/shape depending on you [blue and close to your body when sad, big and yellow when happy, red and spiky when scared, that kind of thing] it's similar to shielding [and psi balls] where your awareness and intention can manipulate your aura.
Magick is intention, not colour. White and black magick is pop culture ways to categorize magick. Some witches will categorize spells by colours [pink for love magick, green for money magick] many more are discovering the racist history of categorizing spells as black and white, as well as, magick being more complex than a binary. You cast a love spell to get your crush to like you [white magick] but in the process, you take them from the person who was going to ask them out [black magick]
All magick has some consequences, and all magick has some level of harm. You need to look at the entire situation and be fine with the consequences. Take money spells. I cast money spells all the time, usually, job related [the business is slow, my hours were reduced, I have a sudden bill appear] the consequence of the spell is working hard and not relaxing as much. In the moment, I'm fine with that... Until I'm three weeks in, exhausted and stressed and wanting to play a video game to unwind but I'm too tired to care. In this case, I'm doing harm to myself in the short term for long-term gains. I never complain [or if I do I call past me a dope lol] because I know this would be the outcome of a money spell. You need to put in the effort to get the reward. Customers come flooding into my business, but they're not going to just hand me money, I have to do my job and help them.
You're new, I understand having a lot of questions. Witchcraft can be confusing because of how diverse the craft is. You've got religious and non-religious witches. Witches who learned from a book [some good books, some bad] and witches who were taught by their parents. Those who preach love and light and those who swear by the duality of magick. Some use crystals, others herbs, some don't even cast spells. It can be very confusing.
