I'm scared of growing up
What is there to be scared about?
I'm scared that I'll fall in love with someone and one day we'll get married
You shouldn't fear those things. Falling in love can't be controlled, but no one can force you to get married.
I like living a young carefree life without those worries. My friends are all getting married and starting their own lives.
Those aren't things to be scared of though! It is just a sign of aging and growing as a person on this world, you should embrace it.