Not to be rude, but your grammar and spelling will hurt you when applying to any institution. You'll want to get an English translator to look over your application and essays to ensure these issues do not affect you.
Other than that, any of the colleges of optometry with a masters or doctoral program will take students from abroad as long as the requirements are met. You'll need to take, or write, the GRE.
If your research includes optometric practice, you'll probably have to prove competency to the state in which you practice, but I have no knowledge on the subject so I won't pretend to. The standards for optometric practice are probably different, so that may affect which countries you are considered an optometrist.
I would suggest contacting some optometry programs and ask them your questions. They'll know far more than the users on this forum.
My name is Alfred Seasonworth. I have recently inherited a large fortune from a distant aunt who hadn't any living benefactors. She happens to be a resident of Lagos, Nigeria - where her husband (my uncle) was once a prominent official in the United Nations.
The problem, sir, is that I do not have a Nigerian citizenship to acquire said fortune. The bureaucratic nature of the government there has prohibited me from obtaining what is rightfully mine.
My humble proposition is that you, a fellow aspiring optometrist, will assist me in this matter. Because we have chosen a similar field of study, I feel a certain kinship and trust with you. The logistics of this pursuit are quite simple: if you can provide me a way to deposit this fortune into a Nigerian bank account, I will share a small (but relatively sizable considering the amount of the fortune) portion of my inheritance.
I will, of course, need to visit Nigeria to accomplish the exchange. Unfortunately at the present time I do not have the funds to do so. My sister was hurt in a motorcycle accident on the way to church to share her baked goods, and I was forced to use my credit and savings to help with her medical bills. She had no insurance, and the medical system of my land is notoriously expensive.
If you can wire me enough money for airfare, I will fly to your beautiful home land and we will both be richer men because of it. We can also discuss our futures in optometry - I have a intimate knowledge of the field, as I am a 24 year old sophmore at a large public university in the Western United States.
Urgency is important in this matter. I fear the fortune may be lost at the hands of the bureaucratic tyrants who control your country. It is in both of our interests that you wire me this money as soon as possible. Please private message me for further details, as I don't want the details of this arrangement to be made public.