Self Doubt with Starting a Business – Model Help

Can you help with the model? I am trying to find a new intentional thought that feels good that will keep pushing me to hit the goal I have a goal to create my own business and my quit current job. I am trying to find my niche through trial and error by using youtube to record videos and blog posts. I am undecided if I will be providing coaching or courses and wanted to test the waters to see what I liked.

C: Business
T: There is no way I am going to make it.
F: Self Doubt
A: Stop taking action; give up
R: No business is created

C: Business
T: ?
F: Determined?
A: record Youtube videos; create blog posts; provide content; ask for feedback
R: Business is created

Other unintentional thoughts that are not serving me:
I don’t even know my niche so how can I create content.
I may not even like what I am doing.
I could quit my job and hate this
I could run out of ideas
There are others doing the same thing
I am living in indecision for niche and what I am providing people so how can I do well.

Help? What are some thoughts that will serve me? Is it ok to just test things by creating videos and seeing where it goes? Or do I need to narrow down an exact niche? I know I want to work with women who have been struggling with weight, over-exercising, and hormonal issues, but there is the other side of me that really loves self development and would love to talk to women about becoming their best self.