Nothing is guaranteed to work

You can’t control whether something succeeds or not. You can mitigate the risk of failure, but you can’t completely control success. The best you can do is make a solid plan and then execute it, given all the knowledge you have obtained up to this point in your life.

Will it work?

I don’t know. The odds of something working change based on how well you have planned, and how well you have learned your market. The better you know your market, the better something will work.

However, nothing is ever 100%, and things may fail, even if the odds of them failing are very low. Whether your launch fails or succeeds, though, you will have new data to add to your database. That new data will make the next launch more predictable, but it will not guarantee success by any stretch of the imagination. It just makes success more likely.

There is nothing more powerful than first-hand data. The more of it you acquire, the more powerful you will become.