Literacy can vary upon culture and place

I studied the English language from my childhood in my country and I thought it would be easier for me to communicate anywhere where English is spoken. But I was surprised when I heard the English spoken here in United States. I had lots of problems regarding accent and the stress while speaking because the English which I learnt in my country was British . And some words are even spelled in different way. I was called an English literate person in my country and I might be called so in United Kingdom as well but I can not consider myself as English literate because of the difference between the way of speaking and writing here in United States.