Default Help! need to unlock galaxy s4 i9505 from Globe tel.. noob here..:(

Previously I purchased a samsung galaxy note 2 from T mobile and I factory unlocked it by following instructions online with service menu and so on.
But now I've purchased this galaxy s4 from Globe carrier in the Philippines and I cant do the same thing as I did with my note 2 before.
I cant access service menu when I type *#0011# I cant go back from service mode menu and cant access any options.
I saw a lot of instances of this with different carriers but I havent found a solution yet.

My questions:

1. Is it possible to flash a firmware from a different carrier to my i9505 globe tel locked? Im scared to brick my phone so I havent tried yet.

2. If my above question is possible, will I be able to access service menu by then?

3. Is it possible to unlock phone by rooting?

Thanks very much! Happy new year!

Samsung galaxy s4 i9505 Globe locked Philippines