When building solo you you have to decide alone, what todo next what color is better what name should I choose, there are so many different decisions to be made. Who do you ask?
Always ask your customers. If you don't have customers yet, you need to get them prior to making any meaningful steps towards a fully-featured product so you can validate your idea.
This forum has a lot of valuable resources on getting and talking to customers, so I recommend you look around.
Best of luck to you. 👍