Writers often have more than one idea. This is quite normal. In this process, you may be wasting your time moving from one idea to another. In order to shorten this process as much as possible, you should initially hold onto an idea and try to advance it as much as possible. You can determine whether your idea is good by what you understand from your feelings as you write and as the novel develops.
That's why it's important to hold on to an idea and push it forward as much as possible and decide on the way.