You know what kills you

Yesterday, I was at Makati to finish my requirements for my new job. While filling out some forms, the HR asked me that do you even know what you're filling out? I was like what the hell is he talking about? I know that these forms are needed for my pre-employment, that's it. He was then pertaining to the monthly deductions from my salary. Yes of course I know that but I dunno EXACTLY how much will be deducted. There's a certain form, I forgot what it is, where I put all the names of our family members as dependents. The HR told me that there's a plan for it and the minimum would be 900 bucks per pax. So that's about 3.6k deduction if I continued my stupidity.

Who would care about deductions and taxes when you're just a student? Now that I am working, even before my first salary, I could already feel the pain of it.  I know that it kills me and I got nothing to do about it.