It’s not common that having new start

[flytothesky]

Hello~ Can you help me say this naturally please?

A: You know, she is 50years old.
It’s not common that having new start studying in her age.
She is the man.

B: Oh, I can’t figure her age through her appearance.

[Raymott]

Hello~ Can you help me say this naturally please?

A: You know, she is 50years old.
It’s not common that having new start studying in her age.
She is the man.

B: Oh, I can’t figure her age through her appearance.

A: You know, she is 50 years old. It isn't common to restart study(ing) at that age. OR It's unusual to start studying again at that age.*
B: Oh, I couldn't tell she was 50 by looking at her.
or B: Really? She doesn't look 50.

My mind boggles at the meaning of "She is the man". I guess in this context it could mean "She is really courageous".

* Actually, it's not.

[flytothesky]

Thanks for your helpful reply

I often heard that "you the man!"

I guess we can use this when the person is outstanding and did something unusual things so I kinda respect that person. Am I right?
Can I say this “Oh, you the man!” to woman? as well?

[vbolton9]

The phrase "you the man" is slang. I would say, "That's great!" instead.
vb

[Daruma]

http://tinyurl.com/nls2gk
the man
a man who is admired or respected as a leader or as the best man in a particular field, sport, etc. ▪ The other players on the team all know that he's the man.
▪ You're the man! = (very informal) You the man! = (very informal + humorous) You da man!

[Raymott]

Can I say this “Oh, you the man!” to woman? as well?

I wouldn't make a habit of it.
Probably not yet in Australia at least. And certainly not "She da man!"