The Tween years for a child are between the ages of 10 years and 13 years old.
So yes a 10 year old is considered a tween and then when you get to 14 and 15 you become a teenager and at 18 to 21 years old you become an adult.
And beyond 21 years old you're just considered an adult.
If you're under 10 years old then you would be considered a kid and at age 4 to 6 you'd be considered a little kid and 2 to 3 years old you'd be a toddler.
But after you get to 10 years old to 13 years old that is when you're considered to be a tween.