First of all I just want to say that you are excellent in the sense that you are donating. But abotu your issue, maybe pick 1 charity which best aligns with your interests and your passions, just 1. Maybe get together all the charity projects you find and put them in a list. Then narrow the choices down. Say for example you find 25 projects. Narrow it down to top 10, then top 5, then top 3, like that. Hope you find my adivce helpful