Where is the best place to find investors for innovative ideas and startups in the earliest stages?

I had an idea two years ago and founded a company. A lot has happened, and a prototype is in the works, but it's difficult to finance everything. Is there perhaps a website where I can specifically contact investors for projects that are still undeveloped? I'm not selling anything yet.

How do you find investors for your product/startup?

I'm currently developing AR glasses that use a different technology than regular glasses and are cheaper to produce than regular glasses. I wanted to look for investors, or rather, find out if it would be possible to find investors for such a product. If so, I'd be interested to know how exactly I could go…