Implementing it would involve some research, and quite large-scale transport engineering. It would also be likely to encounter political opposition in some places, but it would be environmentally clean, and I think it would be wildly popular.
This would be a long-term thing; I'm retired, I'm not up for trying to kick it off, let alone see it through.
I don't know if there is prior art.
How should I proceed?
https://store.nolo.com/products/patent-it-yourself-pat.html
otherwise buy a copy. Reading that will help you understand the possibility and process of getting a patent.
For smaller projects, you can make a kickstarter video and promote that, and wait until knock offs happen, then shutdown the kickstarter and refund the backers. For a large scale transport idea, that's unlikely to work. It can be hard to attract attention to big ideas, but some ways are works of fiction, appearing like a crackpot, building a giant model in the desert (might be the same as item 2), running a fairly successful upstart car company and tweeting anything that comes to mind, etc.
Edit: It's not up to me to judge or anything - and that's far from what I wanted to do, but from what you said until now, this is likely to be how you're being perceived.