Noon: Play a Condition Noon action, reducing its cost by 2, to make Jia a stud.
Noon: Boot a spell on Jia and pay 1 ghost rock to take a Condition from your discard pile into your hand.
Yes. When a card in play has 2 abilities, using one does not prevent you from using the other. As long as you can pay the cost of each ability as you use them.
You may use Jia Mein's ability, to retrieve a condition by booting a spell and paying 1 Ghost Rock.
Later, when you have another opportunity to take an action, you may use Jia's other ability to play the condition at -2 cost to make Jia a stud.
I know you didn't ask this part, but to be thorough:
With Action cards with 2 abilities, like You Had One Job, you choose which action to use as you play it and it's no longer in your hand to play the other ability.