And you're sure you're right how?
Don't forget, truth is a word best avoided in science.
If you can't definitively, absolutely state that you know this to be a fact beyond the shadow of a doubt, that it is true, you can't tell someone else they are wrong.
There are dozens of threads of evidence that all unequivocally show an old earth and an old universe. All of physics, astronomy, geology and several other sciences would have to be completely wrong if the earth were young.
They’re not.
See especially page 22 heading “Rightly Handling the Word of Truth” in the link:
http://www.asa3.org/ASA/resources/Wiens.html