I see two possible situations here; but, IMO, both situations imply that you should probably walk away.
In general: Most people can't start a tech business. Starting a tech business is like being a professional athlete: Most people can't be a professional athlete either!
Situation one:
Early stage businesses need to try a lot of different things against potential customers, and see what sticks. (Look up product-market-fit.) If you aren't at the product-market-fit stage, it doesn't make sense to work on anything that takes longer than a week. (Or a month.)
This is because, if you build something that takes longer than a week (or month,) you're probably building the wrong product.
IE, if this is the situation you're in, you might be better suited to working for a company (startup) that generally has product-market-fit, because you like to build a known thing. There is nothing wrong with this, because this describes the vast majority of technical work.
Situation two:
The CEO probably is a lousy CEO. There is nothing wrong with this, because most people can't be a CEO of a successful startup. It's up to you and your other founder (and investors) to recognize this and figure out what to do. (Replace the CEO, walk away...?)
This is also hard to recognize: I spent over a year of my life working unpaid with someone who initially appeared to be a good CEO. At the end, I realized this person was better off building a sales organization instead of being the CEO. (The big issue was the person I was working with would constantly let their imagination run away, which made it very difficult to plan anything.)
I also more recently spent time with two founders investigating if I should be their CTO. Again, great people and appeared very promising; but, in one of our last conversations, one of them made some off-the-cuff remarks that made me realize they didn't know how to start a "tech" business. Although I wish them the best, I don't think they're going to meet their market window because they're just working on the wrong thing for their talents. (IE, they didn't want to invest enough time in me to build appropriate trust among us; and they didn't know how to hire the right people to build the product they needed.)