I suggest you get out and talk to friends and their friends at your school, about the problems in their fields, that you might be able to help with. They might

I suggest you get out and talk to friends and their friends at your school, about the problems in their fields, that you might be able to help with. They might not identify their problem as needing ML, but you can connect those dots yourself. I think your chance of success is much higher if you work directly with someone who knows the problem domain in depth. Cross-domain work is where its at.