You've had plenty of extremely good advice so far, and you'd do well to take it in board. At the age you are life should feel a lot rosier than you are obviously feeling right now. I was just a little older than when I went through a really bad patch for reason I won't go into now.
The thing I picked up on more than anything was your comment regarding having kids. By the time I was your age I had 2 young daughters and absolutely loved (and stiil do) to bits. The first one was most definitely unplanned and I thought no I'm nowhere near ready to be a Father.
The day she was born stands out as being one of the greatest day's of my life, the pride and overwhelming love I felt the first time I held her cannot be described by words alone. The same was true when her sister was born and when my 2 son's came along a good few years later.
I always used to think I never wanted kids, how wrong I was. They bring so much joy, pride, heartache and at times pain, but I would not swap them for the world. I would lay down my life for them without a second thought.
My point is. The very fact that you are questioning whether you would be a good Father is what would make you just that. Don't dismiss the idea going forwards because you don't think you'd be good enough or you're scared of what "could" happen. They would bring a whole new way of thinking into your life. All I'm asking is, hold this thought for the future.
Right now, do as the others have stated, discover and be yourself. Find and do things that make you feel alive, try new things, experience things you've never done before. Live!!