Question

Why is it that Je suis = I am, but when you say how old you are, it becomes J'ai, which is I am?

Answer 1

When i learned english it was confusing for me too but it’s just the way it is

Answer 2

No j’ai means I have, je suis is i am
The french says I have ___ years (j’ai __ans) They also say I have hot (j’ai chaud) instead of je suis. If you say je suis when talking about how hot you are (temperature wise) then it can mean something very different.