Tackle each problem individually..........
Research the different schools in America.
I imagine it would be difficult to get a job with Singapore Airlines. They may require their pilots to convert their ATPL, but check that out. In some countries, there are nationality restrictions, so as a non-citizen, it may not be possible to get a job there. The aviation industry is different all over the world, so have a look at the PPRuNe forums about the different regions.
Try to get A Levels.
Do an aptitude test, such as the GAPAN one.
See if you can get a Class 1 medical, because without one, you can't fly commercially.
Regards,
Captwannabe