A while back, I invented the TimeCorder, a device for conducting time studies. Today I have 400 of them that I use to conduct profitable corporate time studies. I used to provide advice to other inventors. They usually wanted to sell their ideas. So I often offered to buy their ideas for $5.00. When they reacted strongly, I confessed that I might have been overpaying! "But it's worth millions," they said. "Prove it," I responded.
Ideas are not worth much. Businesses that generate profits or that at least have a large number of people as users are what buyers are interested in.
So take your idea to test the market. Or get some orders for it. Or get a lot of people using your product or service, even if you haven't quite generated revenues or profits yet. Then, you might have something to sell.