Write a Bill about public and enviromental health, it could be about any issue the USA is currently facing.
I was thinking about something that could help/improve the national biodiversity, that could conserve part of the U.S. lands and waters to protect the environment and address climate change by 2030 and other goals necessary to reduce the threats to biodiversity, specially for the upcoming generations.
you can use this bill as an example for some guidance:
https://www.govtrack.us/congress/bills/117/hres69/text