Help With A/C Not Working

#1
Hi,
I bought an 2005 corolla le from a local toyota dealer last year during the winter and forgot to check out the a/c system. As summer came around, i found out the a/c was not working. After a while of procrastination, it was time to look into the issue. I checked the pressure on the low and high side (using manifold gauge) and they both at 0 when the car was not running and they stayed at 0 when the car is running with A/C button on, full fan, and recirculating mode with window open. I'm wondering what i should do next, fill the system with leak-detecting refrigerant or start saving money? How much would it typically cost to bring it to a shop to fix this issue? (both best and worst scenario). If it is possible, i would like to fix it myself while i could learn things as i do that :). I'm comfortable with replacing things in the car. Thanks in advance.
Cheers,
Nguyen
 
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