Not sure how old you are, but you should definitely take a couple college philosophy courses if you can. This is the sort of thing you might well spend several weeks talking about.

One of the most well known texts on the topic is The Importance of What We Care About, which is a collection of 13 famous essays about moral responsibility, including the titular one. You should definitely also read Peter Singer, though it's hard to say exactly where to start. I would probably say Practical Ethics, then The Most Good You Can Do, then The Life You Can Save.

The shorter answer is that I've personally adopted a philosophy (attributed to the Dalai Lama) of essentially "do the best thing you can in each situation you come across in life." In other words, I believe I have a moral imperative to help those I encounter, to treat everyone with kindness, and to make moral choices each time I am faced with a situation, but I do not believe that I have a moral obligation to actively seek out problems and solve them. I do go out of my way to help people I wouldn't have otherwise encountered, but I choose to do so because I want to help, rather than because I have a moral imperative to do so.