1. Eligibility based on the country: To enter the Green Card Lottery, you must be a native of one of the listed countries. See List of Countries By Region Whose Natives Qualify.
Native country is normally the same as the country in which you were born. However, there are two other ways you may be able to qualify:
First: If you were born in a country whose natives are ineligible, but your spouse was born in an eligible country, you can claim your spouse’s country of birth.
In this case the condition is that both of you must enter the United States together.
Second: If you were born in a country whose natives are ineligible, you can 'be charged' to the country of birth of either of your parents as long as neither parent was a resident of the ineligible country at the time of the your birth, provided your parent country of birth qualify for the DV program. See also: FAQ - Question #2.

2. Eligibility based on education or work experience: You must have either:
A high school education or its equivalent, defined as successful completion of a 12-year course of elementary and secondary education; OR
Two years of work experience within the past five years in an occupation requiring at least two years of training or experience to perform. The U.S. Department of Labor’s O*Net OnLine database will be used to determine qualifying work experience. See also: FAQ - Question #13.

If you cannot fulfill both 'native country' and 'education' requirements, you should NOT submit an entry to the Green Card Lottery.