No, and I'll explain why. Taking the time to develop a business plan before starting your small business can help ensure your chances of building a successful business. However, it's far more important to invest your time getting to know your potential customers, learning how you can best solve their relevant problems (rather than making assumptions).
The #1 goal of creating a business plan is to make sure your idea has an established market of potential customers, and give you reasonable confidence that your solution has a high likelihood of helping those customers solve the problem you're hoping to alleviate. Beyond that, a business plan is only effective if it's regularly updated based on real-world learnings you can only gather from actually helping people solve a problem & getting paid to do it.
Instead of creating a business plan before starting your business, I always advise new entrepreneurs to focus instead on solving a real problem they're motivated to tackle, for a few people (and get paid to do it). Once you've validated your business idea by getting paid to solve someone's problem, you have a real business—one that's worthy of then creating a business plan & figuring out how to scale your solution to more people.