It is not too early to start using wrinkle creams, assuming you are using good quality products. As long as you are not looking into medical procedures (Botox as an example) most products should be fine. Note that I am not giving medical advice, only an opinion; should you have any medical concerns, please discuss these with your medical provider.
It's okay. See "What's the difference between A Wrinkle in Time movie and novel". The actors they picked to play the characters are AWESOME!
It is okay to have cellulite. A 16 year old can get rid of it by exercising, and trying some of the over the counter creams available.
Yes you can. Example: Okay, I will go with you.
It would be awkward unless you are using it to draw attention to your opening clause, i.e.: "Of this one thing I am certain: etc... etc..."
It's okay to start a family anytime when you feel ready and have the ability to emotionally and financially support the child.
Yes.
It's okay for you to stay.Yes as in For example, .... and For once in your life, do the right thing.
okay... um... WHY DO YOU WANT TO KNOW?!? okay... um... WHY DO YOU WANT TO KNOW?!?
Fourteen.
Without the fact that the person is called "You" and you are talking about "You" in 3rd person. Is Joe okay? Otherwise it's: Are you okay?
God no.
It will probably start okay but, not run well.