You are correct in using your passion as the starting point in selecting the perfect business for you.
Your passion is expressed in the things you love to do and never get tired of. You can usually pinpoint this to one kind of activity.
Frequently, but not always, you are passionate about things you have a talent for. That is, your natural abilities. This is different than skills you have acquired by hard work and repetitive learning. You can also grow very fond of activities that you have developed skills for. The difference is, one you are totally in love with, and the other you enjoy doing. Define your passion by "Love to Do It", just like meeting a wonderful new girlfriend.
Once you understand your passion, find your Marketable Passion.
Make a list of all the possible things that you could do with your passion. Write them down and make a list, include everything no matter how strange or far-fetched. Then analyze it.
What could you do that will help others solve a problem? What can you do that will provide value? What do people need? What are your resources and opportunities? You'll have to give this a lot of thought and research. Something will stand out like a spotlight!
Your passion, supported by your skills, developed through hard work and applied to a needed product or service will be the right business for you.
I just wrote a blog post on this topic you might care to look at:
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The Passionate Entrepreneur
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