We can’t answer this question responsibly until we understand your idea, business, market, users etc.
While it’s really hard to know the specific time the software project will take, we can usually set a responsible project timeline before you ever hire us.
It’s also important to keep in mind that most projects get broken up into multiple phases. During the first phase of the development, our goal is always to focus on the highest value features and architect something that sets up for future phases.