Despite being the third most common resolution last year according to Statista, it's terribly unspecific. Resolutions in general are aimed at improving yourself, so saying you resolve to "be a better person" is a bit like saying you "resolve to resolve something." As we established earlier, specific goals are better. For example, that might include:
"I'm going to donate X% of my income this year." Giving to charities has never been easier. For example, Amazon has a program wherein you can donate 0.5% of your purchase to a charity of your choice. You can even use this extension to always shop through that site. If you want to make a positive change for others, this is a great way to start. There are plenty of other ways to contribute to charities without spending any extra money.
"I'm going to work on being less angry/more self-controlled/more attentive." Being a "better person" is vague. "I'd really like to stop punching so much stuff" is specific. If that's your problem, learn to manage your seething rage productively. Or you can try to work on your self-control. Or improve your attention span. Whatever you do, narrow down the field.
"I will meditate once a day." It may sound silly but meditation has a host of psychological and physical benefits associated with it. If you want to stick with the broad strokes "be a better person" goal, meditation is a great specific way to do that. It can reduce stress, improve memory, boost creativity, and plenty more. Plus, getting started is dead simple.