I want to work in a call center....

You can try SITEL. I suggest you first practice answering interviews. There are a lot of sample interviews online. But don't memorize, it would only serve as a guide. Try researching the company because some interviewers may ask their applicants what they know about the company they're applying for. Anyway don't lose hope if you didn't pass. There are lots of call centers out there out there. Before I enter the call center industry, I have had a training at Call Center Academy in Pasig. They give scholarships if you pass. You may also try TESDA at Taguig. After training with these institutions, they will endorse you to different call centers. Good luck!