I don't get Numerology😕

So most of you people know Astrology, which I actually explained a bit about and  which you can read that post by clicking here.  So todays topic  is me trying to figure out how and what numerology is.  From what I know numerology is kind of like astrology, it tells you your personality and how your like based on your life path number of something.  I just don't understand how to find that number.  Some websites say that numerology is based on your birthday.  You know how lets say you where born on January 13, 1993.  Since January is the first month it would be 1.  So 1+1+3+1+9+9+3.  The answer would be 27.  Then you add 2+7.  Which becomes 9, and that would be your life path number or whatever.  But then I see other websites and they where like it has to do with your name.  So apparently each letter is like assigned to a number 1-10.  Like A would be 1 and the letter B would be number 2.  So then you would put together all the numbers your name created a kind of code.  You would then add all those numbers up and you get your life path number.  Then if you wanted to find this other number you add up the numbers that where consonants and do the same with vowels and you would get other numbers.  So my question is, Which way is the right way to find your number and what does your name have to do with your personality or life?  Like what if I was named something else?  That would probably change my path number.  And what if you where a girl named Julie, but if you where a boy your parents would name you Justin, that wouldn't mean your personality would change, would it?  

Well I hope y'all enjoyed me ranting about not knowing something.  So subscribe, share, and comment down below if you can help me understand numerology.  And before I forget, there is a gadget under this post that says reactions and you can chose one of the reactions provided if you think it is informative, cool, or funny.  So you can do that and I will see you guys tomorrow, bye.