You know, the first sentence gives many people trouble, and I often advise my students to write their content and then go back to write the introduction. There are no rules that say you must start at the beginning, and I frequently start my writing somewhere in the middle.
However, if you feel that you cannot go on until you get that first sentence down, there are plenty of easy ways to begin. One way is to place yourself in a historical context. For example, I might begin by saying something like, "I was born at the end of the post-WWII era." Another way is to place yourself within the context of your family, for example, "I was born into a family of four." Still another way is to quickly convey a sense of your personality, maybe something like, "I was born shy." Given that you only have one page to convey your autobiographical details, you will want to draw the reader in with some sense of who you are, and beginning in one of those ways accomplishes that for you.
What you do not want to do is say, "My name is..." or "This paper will discuss ..." because we do not "announce" ourselves in academic writing. Begin with an assertion about yourself, and I do believe you will be fine.