Everything starts from an idea. And it's important but it's nothing without execution.
You should start fast and start with proper tools. Do not make it perfect and do not re-invent the wheel.
Move fast. But have a solid foundation for your product is crucial.
Get 1st feature done. Validate it fast. Don't spend time on things that doesn't matter.
With the passage of time more and more days and stories will be added. Enjoy the journey, not the goal.