Always write down short and powerful sentences. start this way
"It is to inform you that I got an opportunity of higher studies abroad. I am highly interested to avail it."
I like this advice! That is a powerful way to communicate.
Grisbel, what is your intended outcome? That is always the question to ask. With anything you do, ask yourself what you want to cause. This is already well written, so if you want to improve it you have to go back to your purpose. Add a sentence that will get your desired result.