I am not a professional by my own view, but nor am I unfamiliar with magic and entities. What I do know is this, for every positove and negative, there is a symbolism amd an entity. You don’t have to search far, but you do need to keep yourself protected. As mentioned above, there are those who seek strengthening their vessels. Thats an entirely different matter, and not one I personally recommend. There are, however, others that would be more than willing to help. I would recommend doing some research to find your safest route, and most compatible entity.
Now it is also entirely possible to take all the negative energies someone has put on you and your life, and send it back mixed with some of your own. But that requires both will and desire. And a lot of it. No candles are needed nor any ingredients, just a strong mental image of the person and what you want to see happen, as well as topping off your emotions, i find the bigger the emotion, the bigger the desire, and the stronger the cast. But that is me personally and can not gauruntee it will be effective with you. Being a Cancer, I heavily rely on my emotions to fuel everything I do magically.