How to find a significant other?

I have been single for years now and I want to find someone with whom I can love and care about and even spend the rest of life with. I am 28 yo with a good job in an IT company, I work remotely so I spend most my time at home, I do go out with my female friends from time to time to restaurants, coffee shop or fancy lounges. I do take care of how I look and dress but I look so young compared to my age, some say that I look like a 17 yo even tho I dress my age. when it comes to social media I don't post. I have one profile picture and that's it, why? I am not photogenic and I don't know how to take good pictures also I am a private person I don't like showing off where I go or where I eat... Sometimes I go out for a walk or just sit alone in a coffee shop reading or writing. The men that approach me are usually old men or Fuckboys, so how can I change that how can I meet a suitable man that wants a serious relationship that could lead to marriage?

How to find a significant other?
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