[Bhurn00985]

Start by not contributing to the mess, so do no harm principles are important in one's personal life. Yes that includes being careful with natural resources.

After that, consider that very large charities might have considerable overheard and their practical aid on the ground very limited, or very politicized.

Local community organizations might have higher needs, have and allow you to make more more impact, though they will not have the marketing and outreach capabilities of a large organization. But...finding those might take a little more work on your side. As you want to do good in the short term, and I assume you wouldn't mind a local focus and getting the feeling you're contributing something, you could get in touch with e.g. a city social services department, they probably know which organizations exist close to you which could use some help.