Well it depends on whether you are a girl or a boy. I am a girl and when I was 13 years old I loved to make things, so I learned to sew and I made all kinds of clothes and I also learned to crochet and made things that way too. Another great hobby for a young girl is jewelry making. All of these things you can learn and it doesn't take a long time to learn the basics. For a boy, you might want to try building things like model cars or trains. You may even like to learn to sculpt things like in carpentry.
I'm a girl so if your a boy I don't know if you would like it so. I like to explore and make a lot of things. I make things with sticks, I made a North South East amd West sign, a make spears, and I use them as decorations for my room or with some of my spears I go exploring and who knows what I'll bump into! So yeah.
For a boy, try building model planes and cars, then paint them. For girls, try reading many different magazines, then cut out your favorite articles and make a journal or scrapbook. I've actually done both in my life. I read mostly flying magazines and hunting & fishing mags. I have filled 4 scrapbooks so far. I like to look back at them every so often to remind me of the things I thought were important back then.