Masters & Training?

Your post is not quite clear and I think that's why you are not getting responses. In trying to understand what you just posted, it seems like you're still a student interested in eventually starting a Master's degree program in the Philippines and that down the line, you see yourself being in the US.

You basically can do whatever you want as far as pursuing further education. However, you will need a period of on the job training when you start working in the US regardless. If you are attending school and starting a new job at the same time, the nurse manager must be aware of that arrangement and most likely would prefer that your schooling does not interfere with your work commitment.

A Master's degree obtained in the Philippines can not be taken away from you. It "is" a Master's degree. However, job requirements in any nursing position looks at not only on your educational qualifications but also your nursing experience. You can not, for instance, assume a leadership role as a nurse just because you have a Master's degree if you don't have the experience to back up your abilities to function in such a role.